Jack has 40% more erasers than Howard. Zeph has 80% the number of erasers Jack has.
- What is the ratio of the number of Howard's erasers to the number of Zeph's erasers?
- If the total number of erasers of Jack's and Zeph's is 380 more than Howard's, how many erasers does Jack have?
Jack |
Howard |
Zeph |
7x5 |
5x5 |
|
5x7 |
|
4x7 |
35 u |
25 u |
28 u |
100% + 40% = 140%
140% =
140100 =
75 Jack's erasers : Howard's erasers = 35 : 25
80% =
80100 =
45 Zeph's erasers : Jack's erasers = 28 : 35
Howard's erasers: Zeph's erasers = 25 : 28 (a)
Jack's erasers + Zeph's erasers = 35 u + 28 u = 63 u
Howard's erasers = 25 u
63 u - 25 u = 380
38 u = 380
1 u = 380 ÷ 38 = 10
Number of Jack's erasers
= 35 u
= 35 x 10
= 350 (b)
Answers: (a) 25 : 28; (b) 350