Sasi Math (Revised for 1024)

Scroll:Distance, Time and Speed >> Distance, Time & Speed >> ps (689)

Written Instructions:

For each Multiple Choice Question (MCQ), four options are given. One of them is the correct answer. Make your choice (1,2,3 or 4). Write your answers in the brackets provided..

For each Short Answer Question(SAQ) and Long Answer Question(LAQ), write your answers in the blanks provided.

Leave your answers in the simplest form or correct to two decimal places.

A motorist travelled $\frac{2}{5}$ of his journey at 95 $\frac{km}{h.}$ After which, he changed his speed to 114 $\frac{km}{h}$ and completed the rest of his journey in 2 $\frac{1}{2}$ hours. Given that the motorist reached his destination at 1.30 p.m., at what time did he start his journey

Answer:_______________

Mr Lim drove at 30 $\frac{km}{h}$ for $\frac{1}{5}$ of the journey and drove the remaining 120 km at 60 $\frac{km}{h}$ . Calculate his average speed for the whole journey. Express your answer corrected to the nearest 2 decimal places.

$\frac{km}{h}$

Answer:_______________

A motorist travelled $\frac{2}{5}$ of his journey at 112 $\frac{km}{h.}$ After which, he changed his speed to 96 $\frac{km}{h}$ and completed the rest of his journey in 3 $\frac{1}{2}$ hours. Given that the motorist reached his destination at 1.30 p.m., at what time did he start his journey

Answer:_______________

Mr Lim drove at 60 $\frac{km}{h}$ for $\frac{1}{5}$ of the journey and drove the remaining 240 km at 60 $\frac{km}{h}$ . Calculate his average speed for the whole journey. Express your answer corrected to the nearest 2 decimal places.

$\frac{km}{h}$

Answer:_______________

A motorist travelled $\frac{2}{5}$ of his journey at 105 $\frac{km}{h.}$ After which, he changed his speed to 90 $\frac{km}{h}$ and completed the rest of his journey in 3 $\frac{1}{2}$ hours. Given that the motorist reached his destination at 1.30 p.m., at what time did he start his journey

Answer:_______________

Mr Lim drove at 75 $\frac{km}{h}$ for $\frac{1}{5}$ of the journey and drove the remaining 300 km at 60 $\frac{km}{h}$ . Calculate his average speed for the whole journey. Express your answer corrected to the nearest 2 decimal places.

$\frac{km}{h}$

Answer:_______________

A motorist travelled $\frac{2}{5}$ of his journey at 55 $\frac{km}{h.}$ After which, he changed his speed to 66 $\frac{km}{h}$ and completed the rest of his journey in 2 $\frac{1}{2}$ hours. Given that the motorist reached his destination at 1.30 p.m., at what time did he start his journey

Answer:_______________

Mr Lim drove at 80 $\frac{km}{h}$ for $\frac{1}{5}$ of the journey and drove the remaining 320 km at 80 $\frac{km}{h}$ . Calculate his average speed for the whole journey. Express your answer corrected to the nearest 2 decimal places.

$\frac{km}{h}$

Answer:_______________

A motorist travelled $\frac{2}{5}$ of his journey at 60 $\frac{km}{h.}$ After which, he changed his speed to 72 $\frac{km}{h}$ and completed the rest of his journey in 2 $\frac{1}{2}$ hours. Given that the motorist reached his destination at 1.30 p.m., at what time did he start his journey

Answer:_______________

10)

Mr Lim drove at 45 $\frac{km}{h}$ for $\frac{1}{5}$ of the journey and drove the remaining 360 km at 60 $\frac{km}{h}$ . Calculate his average speed for the whole journey. Express your answer corrected to the nearest 2 decimal places.

$\frac{km}{h}$

Answer:_______________

Answer: 9.00 a.m.

SOLUTION 1 :

Step 1:	1h	→	114 km
	2 $\frac{1}{2}$ h	ï»¿→	2 $\frac{1}{2}$ x 114 km
		=	285 km

Step 2: 1- $\frac{2}{5}$ = $\frac{3}{5}$

Step 3:	$\frac{3}{5}$ of the journey	→	285 km
	$\frac{1}{5}$ of the journey	ï»¿→	285 km ÷ 3
		=	95 km
	$\frac{2}{5}$ of the journey	→	2 x 95 km
		=	190 km

Step 4:	Time taken to complete the first $\frac{2}{5}$ of the journey	→	190 km ÷ 95 $\frac{km}{h}$
		=	2 h

Step 5:	Total travel time	→	2 $\frac{1}{2}$ h + 2 h
		=	4 $\frac{1}{2}$ h

Step 6:	Time the motorist started his journey	→	1.30 p.m. - 4 $\frac{1}{2}$ h
		=	9.00 a.m.

Answer: 50.00 $\frac{km}{h}$

SOLUTION 1 :

Step 1:	Time to cover the last 120 km	→	120 km ÷ 60 $\frac{km}{h}$
		ï»¿=	2 h

Step 2: 1 - $\frac{1}{5}$ = $\frac{4}{5}$

Step 3:	$\frac{4}{5}$ of the journey	→	120 km
	$\frac{1}{5}$ of the journey	→	120 km ÷ 4
		=	30 km
	$\frac{5}{5}$ of the journey	→	5 x 30 km
		=	150 km

Step 4:	Time to cover the first $\frac{1}{5}$ of the journey	→	30 km ÷ 30 $\frac{km}{h}$
		=	1 h

Step 5:	Total time for the whole journey	→	2 h + 1 h
		=	3 h

Step 6:	Average speed	→	150 km ÷ 3 h
		=	50 $\frac{km}{h}$
		≈	50.00 $\frac{km}{h}$

Answer: 8.00 a.m.

SOLUTION 1 :

Step 1:	1h	→	96 km
	3 $\frac{1}{2}$ h	ï»¿→	3 $\frac{1}{2}$ x 96 km
		=	336 km

Step 2: 1- $\frac{2}{5}$ = $\frac{3}{5}$

Step 3:	$\frac{3}{5}$ of the journey	→	336 km
	$\frac{1}{5}$ of the journey	ï»¿→	336 km ÷ 3
		=	112 km
	$\frac{2}{5}$ of the journey	→	2 x 112 km
		=	224 km

Step 4:	Time taken to complete the first $\frac{2}{5}$ of the journey	→	224 km ÷ 112 $\frac{km}{h}$
		=	2 h

Step 5:	Total travel time	→	3 $\frac{1}{2}$ h + 2 h
		=	5 $\frac{1}{2}$ h

Step 6:	Time the motorist started his journey	→	1.30 p.m. - 5 $\frac{1}{2}$ h
		=	8.00 a.m.

Answer: 60.00 $\frac{km}{h}$

SOLUTION 1 :

Step 1:	Time to cover the last 240 km	→	240 km ÷ 60 $\frac{km}{h}$
		ï»¿=	4 h

Step 2: 1 - $\frac{1}{5}$ = $\frac{4}{5}$

Step 3:	$\frac{4}{5}$ of the journey	→	240 km
	$\frac{1}{5}$ of the journey	→	240 km ÷ 4
		=	60 km
	$\frac{5}{5}$ of the journey	→	5 x 60 km
		=	300 km

Step 4:	Time to cover the first $\frac{1}{5}$ of the journey	→	60 km ÷ 60 $\frac{km}{h}$
		=	1 h

Step 5:	Total time for the whole journey	→	4 h + 1 h
		=	5 h

Step 6:	Average speed	→	300 km ÷ 5 h
		=	60 $\frac{km}{h}$
		≈	60.00 $\frac{km}{h}$

Answer: 8.00 a.m.

SOLUTION 1 :

Step 1:	1h	→	90 km
	3 $\frac{1}{2}$ h	ï»¿→	3 $\frac{1}{2}$ x 90 km
		=	315 km

Step 2: 1- $\frac{2}{5}$ = $\frac{3}{5}$

Step 3:	$\frac{3}{5}$ of the journey	→	315 km
	$\frac{1}{5}$ of the journey	ï»¿→	315 km ÷ 3
		=	105 km
	$\frac{2}{5}$ of the journey	→	2 x 105 km
		=	210 km

Step 4:	Time taken to complete the first $\frac{2}{5}$ of the journey	→	210 km ÷ 105 $\frac{km}{h}$
		=	2 h

Step 5:	Total travel time	→	3 $\frac{1}{2}$ h + 2 h
		=	5 $\frac{1}{2}$ h

Step 6:	Time the motorist started his journey	→	1.30 p.m. - 5 $\frac{1}{2}$ h
		=	8.00 a.m.

Answer: 62.50 $\frac{km}{h}$

SOLUTION 1 :

Step 1:	Time to cover the last 300 km	→	300 km ÷ 60 $\frac{km}{h}$
		ï»¿=	5 h

Step 2: 1 - $\frac{1}{5}$ = $\frac{4}{5}$

Step 3:	$\frac{4}{5}$ of the journey	→	300 km
	$\frac{1}{5}$ of the journey	→	300 km ÷ 4
		=	75 km
	$\frac{5}{5}$ of the journey	→	5 x 75 km
		=	375 km

Step 4:	Time to cover the first $\frac{1}{5}$ of the journey	→	75 km ÷ 75 $\frac{km}{h}$
		=	1 h

Step 5:	Total time for the whole journey	→	5 h + 1 h
		=	6 h

Step 6:	Average speed	→	375 km ÷ 6 h
		=	62.5 $\frac{km}{h}$
		≈	62.50 $\frac{km}{h}$

Answer: 9.00 a.m.

SOLUTION 1 :

Step 1:	1h	→	66 km
	2 $\frac{1}{2}$ h	ï»¿→	2 $\frac{1}{2}$ x 66 km
		=	165 km

Step 2: 1- $\frac{2}{5}$ = $\frac{3}{5}$

Step 3:	$\frac{3}{5}$ of the journey	→	165 km
	$\frac{1}{5}$ of the journey	ï»¿→	165 km ÷ 3
		=	55 km
	$\frac{2}{5}$ of the journey	→	2 x 55 km
		=	110 km

Step 4:	Time taken to complete the first $\frac{2}{5}$ of the journey	→	110 km ÷ 55 $\frac{km}{h}$
		=	2 h

Step 5:	Total travel time	→	2 $\frac{1}{2}$ h + 2 h
		=	4 $\frac{1}{2}$ h

Step 6:	Time the motorist started his journey	→	1.30 p.m. - 4 $\frac{1}{2}$ h
		=	9.00 a.m.

Answer: 80.00 $\frac{km}{h}$

SOLUTION 1 :

Step 1:	Time to cover the last 320 km	→	320 km ÷ 80 $\frac{km}{h}$
		ï»¿=	4 h

Step 2: 1 - $\frac{1}{5}$ = $\frac{4}{5}$

Step 3:	$\frac{4}{5}$ of the journey	→	320 km
	$\frac{1}{5}$ of the journey	→	320 km ÷ 4
		=	80 km
	$\frac{5}{5}$ of the journey	→	5 x 80 km
		=	400 km

Step 4:	Time to cover the first $\frac{1}{5}$ of the journey	→	80 km ÷ 80 $\frac{km}{h}$
		=	1 h

Step 5:	Total time for the whole journey	→	4 h + 1 h
		=	5 h

Step 6:	Average speed	→	400 km ÷ 5 h
		=	80 $\frac{km}{h}$
		≈	80.00 $\frac{km}{h}$

Answer: 9.00 a.m.

SOLUTION 1 :

Step 1:	1h	→	72 km
	2 $\frac{1}{2}$ h	ï»¿→	2 $\frac{1}{2}$ x 72 km
		=	180 km

Step 2: 1- $\frac{2}{5}$ = $\frac{3}{5}$

Step 3:	$\frac{3}{5}$ of the journey	→	180 km
	$\frac{1}{5}$ of the journey	ï»¿→	180 km ÷ 3
		=	60 km
	$\frac{2}{5}$ of the journey	→	2 x 60 km
		=	120 km

Step 4:	Time taken to complete the first $\frac{2}{5}$ of the journey	→	120 km ÷ 60 $\frac{km}{h}$
		=	2 h

Step 5:	Total travel time	→	2 $\frac{1}{2}$ h + 2 h
		=	4 $\frac{1}{2}$ h

Step 6:	Time the motorist started his journey	→	1.30 p.m. - 4 $\frac{1}{2}$ h
		=	9.00 a.m.

10)

Answer: 56.25 $\frac{km}{h}$

SOLUTION 1 :

Step 1:	Time to cover the last 360 km	→	360 km ÷ 60 $\frac{km}{h}$
		ï»¿=	6 h

Step 2: 1 - $\frac{1}{5}$ = $\frac{4}{5}$

Step 3:	$\frac{4}{5}$ of the journey	→	360 km
	$\frac{1}{5}$ of the journey	→	360 km ÷ 4
		=	90 km
	$\frac{5}{5}$ of the journey	→	5 x 90 km
		=	450 km

Step 4:	Time to cover the first $\frac{1}{5}$ of the journey	→	90 km ÷ 45 $\frac{km}{h}$
		=	2 h

Step 5:	Total time for the whole journey	→	6 h + 2 h
		=	8 h

Step 6:	Average speed	→	450 km ÷ 8 h
		=	56.25 $\frac{km}{h}$
		≈	56.25 $\frac{km}{h}$