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 126 $\frac{km}{h.}$ After which, he changed his speed to 108 $\frac{km}{h}$ 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 480 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 65 $\frac{km}{h.}$ After which, he changed his speed to 78 $\frac{km}{h}$ 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 100 $\frac{km}{h}$ for $\frac{1}{5}$ of the journey and drove the remaining 400 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 80 $\frac{km}{h.}$ After which, he changed his speed to 96 $\frac{km}{h}$ 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 45 $\frac{km}{h}$ for $\frac{1}{5}$ of the journey and drove the remaining 180 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 133 $\frac{km}{h.}$ After which, he changed his speed to 114 $\frac{km}{h}$ 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 600 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 90 $\frac{km}{h.}$ After which, he changed his speed to 108 $\frac{km}{h}$ 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 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:_______________

Answer: 8.00 a.m.

SOLUTION 1 :

Step 1:	1h	→	108 km
	3 $\frac{1}{2}$ h	ï»¿→	3 $\frac{1}{2}$ x 108 km
		=	378 km

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

Step 3:	$\frac{3}{5}$ of the journey	→	378 km
	$\frac{1}{5}$ of the journey	ï»¿→	378 km ÷ 3
		=	126 km
	$\frac{2}{5}$ of the journey	→	2 x 126 km
		=	252 km

Step 4:	Time taken to complete the first $\frac{2}{5}$ of the journey	→	252 km ÷ 126 $\frac{km}{h}$
		=	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: 75.00 $\frac{km}{h}$

SOLUTION 1 :

Step 1:	Time to cover the last 480 km	→	480 km ÷ 80 $\frac{km}{h}$
		ï»¿=	6 h

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

Step 3:	$\frac{4}{5}$ of the journey	→	480 km
	$\frac{1}{5}$ of the journey	→	480 km ÷ 4
		=	120 km
	$\frac{5}{5}$ of the journey	→	5 x 120 km
		=	600 km

Step 4:	Time to cover the first $\frac{1}{5}$ of the journey	→	120 km ÷ 60 $\frac{km}{h}$
		=	2 h

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

Step 6:	Average speed	→	600 km ÷ 8 h
		=	75 $\frac{km}{h}$
		≈	75.00 $\frac{km}{h}$

Answer: 9.00 a.m.

SOLUTION 1 :

Step 1:	1h	→	78 km
	2 $\frac{1}{2}$ h	ï»¿→	2 $\frac{1}{2}$ x 78 km
		=	195 km

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

Step 3:	$\frac{3}{5}$ of the journey	→	195 km
	$\frac{1}{5}$ of the journey	ï»¿→	195 km ÷ 3
		=	65 km
	$\frac{2}{5}$ of the journey	→	2 x 65 km
		=	130 km

Step 4:	Time taken to complete the first $\frac{2}{5}$ of the journey	→	130 km ÷ 65 $\frac{km}{h}$
		=	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: 83.33 $\frac{km}{h}$

SOLUTION 1 :

Step 1:	Time to cover the last 400 km	→	400 km ÷ 80 $\frac{km}{h}$
		ï»¿=	5 h

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

Step 3:	$\frac{4}{5}$ of the journey	→	400 km
	$\frac{1}{5}$ of the journey	→	400 km ÷ 4
		=	100 km
	$\frac{5}{5}$ of the journey	→	5 x 100 km
		=	500 km

Step 4:	Time to cover the first $\frac{1}{5}$ of the journey	→	100 km ÷ 100 $\frac{km}{h}$
		=	1 h

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

Step 6:	Average speed	→	500 km ÷ 6 h
		=	83.33333 $\frac{km}{h}$
		≈	83.33 $\frac{km}{h}$

Answer: 9.00 a.m.

SOLUTION 1 :

Step 1:	1h	→	96 km
	2 $\frac{1}{2}$ h	ï»¿→	2 $\frac{1}{2}$ x 96 km
		=	240 km

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

Step 3:	$\frac{3}{5}$ of the journey	→	240 km
	$\frac{1}{5}$ of the journey	ï»¿→	240 km ÷ 3
		=	80 km
	$\frac{2}{5}$ of the journey	→	2 x 80 km
		=	160 km

Step 4:	Time taken to complete the first $\frac{2}{5}$ of the journey	→	160 km ÷ 80 $\frac{km}{h}$
		=	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: 56.25 $\frac{km}{h}$

SOLUTION 1 :

Step 1:	Time to cover the last 180 km	→	180 km ÷ 60 $\frac{km}{h}$
		ï»¿=	3 h

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

Step 3:	$\frac{4}{5}$ of the journey	→	180 km
	$\frac{1}{5}$ of the journey	→	180 km ÷ 4
		=	45 km
	$\frac{5}{5}$ of the journey	→	5 x 45 km
		=	225 km

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

Step 5:	Total time for the whole journey	→	3 h + 1 h
		=	4 h

Step 6:	Average speed	→	225 km ÷ 4 h
		=	56.25 $\frac{km}{h}$
		≈	56.25 $\frac{km}{h}$

Answer: 8.00 a.m.

SOLUTION 1 :

Step 1:	1h	→	114 km
	3 $\frac{1}{2}$ h	ï»¿→	3 $\frac{1}{2}$ x 114 km
		=	399 km

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

Step 3:	$\frac{3}{5}$ of the journey	→	399 km
	$\frac{1}{5}$ of the journey	ï»¿→	399 km ÷ 3
		=	133 km
	$\frac{2}{5}$ of the journey	→	2 x 133 km
		=	266 km

Step 4:	Time taken to complete the first $\frac{2}{5}$ of the journey	→	266 km ÷ 133 $\frac{km}{h}$
		=	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 600 km	→	600 km ÷ 60 $\frac{km}{h}$
		ï»¿=	10 h

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

Step 3:	$\frac{4}{5}$ of the journey	→	600 km
	$\frac{1}{5}$ of the journey	→	600 km ÷ 4
		=	150 km
	$\frac{5}{5}$ of the journey	→	5 x 150 km
		=	750 km

Step 4:	Time to cover the first $\frac{1}{5}$ of the journey	→	150 km ÷ 75 $\frac{km}{h}$
		=	2 h

Step 5:	Total time for the whole journey	→	10 h + 2 h
		=	12 h

Step 6:	Average speed	→	750 km ÷ 12 h
		=	62.5 $\frac{km}{h}$
		≈	62.50 $\frac{km}{h}$

Answer: 9.00 a.m.

SOLUTION 1 :

Step 1:	1h	→	108 km
	2 $\frac{1}{2}$ h	ï»¿→	2 $\frac{1}{2}$ x 108 km
		=	270 km

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

Step 3:	$\frac{3}{5}$ of the journey	→	270 km
	$\frac{1}{5}$ of the journey	ï»¿→	270 km ÷ 3
		=	90 km
	$\frac{2}{5}$ of the journey	→	2 x 90 km
		=	180 km

Step 4:	Time taken to complete the first $\frac{2}{5}$ of the journey	→	180 km ÷ 90 $\frac{km}{h}$
		=	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: 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 $\frac{km}{h}$