Number And Algebra - Chapter 7 Applying Ratios And Rates - Nelson Think Math Page 16
ADVERTISEMENT
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32N E L S O N T H I N K M A T H S
8
A u s t r a l i a n C u r r i c u l u m
for the
Example
15
A pile of sand takes 2 men 36 minutes to barrow from the front to the back of a house. How
long would it have taken 3 men?
Solution
The time to move the sand is the opposite ratio
to the number of men. Write this as equivalent
1st number of men
2nd time
¼
ratios.
2nd number of men
1st time
2
2nd time
Put in the numbers.
¼
3
36
Cross-multiply the ratios.
2nd time 3 3 ¼ 2 3 36 ¼ 72 minutes
Divide by 3.
2nd time ¼ 72 4 3 ¼ 24 minutes
Write the answer.
3 men would have taken 24 minutes.
Exercise 7.2
Ratios
Understanding
1
The drawing below shows a beach scene. Find the ratios below, simplifying if necessary.
Extra questions
Exercise 7.2
MAT08NAEQ00024
See Example 8
a
Beach balls to surfboards
b
Boys : surfboards
c
Beach balls to girls
d
Boys with hats : girls
e
Girls to boys with hats
f
Boys with hats to girls with hats
g
Girls with hats to boys with hats
h
Beach towels to umbrellas
253
9780170214148
ADVERTISEMENT
0 votes
Related Articles
Related forms
Related Categories
Parent category: Education