Joelle is 20% heavier than John. Kathy is 30% lighter than John. Joelle is 50 kg heavier than Kathy. What is John's mass?
| Joelle |
John |
Kathy |
| 120% |
100% |
|
| |
100% |
70% |
| 12 u |
10 u |
7 u |
Joelle's mass compared to John's mass in percent
= 100% + 20%
= 120%
Kathy's mass compared to John's mass in percent
= 100% - 30%
= 70%
120% =
120100 =
121070% =
70100 =
710John's mass is the repeated identity. Make John's mass the same.
John's mass = 10 u
Mass that Joelle has more than Kathy
= 12 u - 7 u
= 5 u
5 u = 50
1 u = 50 ÷ 5 = 10
John's mass
= 10 u
= 10 x 10
= 100 kg
Answer(s): 100 kg
