Japheth has 10 stamps more than Kathy. How many stamps must Kathy get from Japheth so that she has 30 stamps more than him?
| |
Japheth |
Kathy |
Comparing Japheth
and Kathy
at first |
10 more |
|
| Before |
|
|
| Change |
- ? |
+ ? |
| After |
|
|
Comparing Japheth
and Kathy
in the end |
|
30 more |
If Japheth gives 10 stamps to Kathy, she will have 10 more stamps than him. However, Kathy must have 30 more stamps than Japheth in the end. So, Japheth has to give Kathy more stamps.
Number of more stamps that Japheth has to give to Kathy
= (30 - 10) ÷ 2
= 20 ÷ 2
= 10
So after giving 10 stamps to Kathy, Japheth has to give her another 10 more stamps so that she has 30 stamps more than him.
Total number of stamps that Kathy needs to get from Japheth
= 10 + 10
= 20
Answer(s): 20
