The average height of a group of 9 girls is 106 cm. When Risa and Lynn left the group, the average height decreased by 3 cm. What is Risa and Lynn's total height?
| |
9 girls |
7 girls |
| Number |
9 |
7 |
| Value |
106 |
103 |
| Total value |
954 |
721 |
Total number of girls after 2 girls left the group
= 9 - 2
= 7
New average height after 2 girls left the group
= 106 - 3
= 103 cm
Total height of 9 girls
= 9 x 106
= 954 cm
Total height of 7 girls
= 7 x 103
= 721 cm
Total height of Risa and Lynn
= 954 - 721
= 233 cm
Answer(s): 233 cm
