The average height of a group of 9 girls is 131 cm. When Kathy and Penelope left the group, the average height decreased by 3 cm. What is Kathy and Penelope's total height?
| |
9 girls |
7 girls |
| Number |
9 |
7 |
| Value |
131 |
128 |
| Total value |
1179 |
896 |
Total number of girls after 2 girls left the group
= 9 - 2
= 7
New average height after 2 girls left the group
= 131 - 3
= 128 cm
Total height of 9 girls
= 9 x 131
= 1179 cm
Total height of 7 girls
= 7 x 128
= 896 cm
Total height of Kathy and Penelope
= 1179 - 896
= 283 cm
Answer(s): 283 cm
