Yen has 25% as many pens as Hazel. Hazel has 130% as many pens as Risa. If Hazel gives 12 pens to Risa, both will then have an equal number of pens. Find the average number of pens the three of them have.
Yen |
Hazel |
Risa |
1x13 |
4x13 |
|
|
13x4 |
10x4 |
13 u |
52 u |
40 u |
25% =
25100 =
14130% =
130100=
1310The number of pens that Yen has is repeated. Make the number of pens that Yen has the same. LCM of 4 and 13 is 52.
|
Hazel |
Risa |
Total |
Before |
52 u |
40 u |
92 u |
Change |
- 6 u |
+ 6 u |
|
After |
46 u |
46 u |
92 u |
Total number of pens that Hazel and Risa have
= 52 u + 40 u
= 92 u
After Hazel gives to Risa, both of them will have the same number of pens.
The total number of pens that Hazel and Risa have remains unchanged.
Number of pens that each of them will have
= 92 u ÷ 2
= 46 u
Number of pens that Hazel gives to Risa
= 52 u - 46 u
= 6 u
6 u = 12
1 u = 12 ÷ 6 = 2
Total number of pens that three of them have
= 92 u + 13 u
= 105 u
Average number of pens that each of them have
= 105 u ÷ 3
= 35 u
= 35 x 2
= 70
Answer(s): 70