The average height of a group of 7 girls is 123 cm. When Olivia and Linda joined the group, the average height increased by 8 cm. What is Olivia and Linda's total height?
| |
7 girls |
9 girls |
| Number |
7 |
9 |
| Value |
123 |
131 |
| Total value |
861 |
1179 |
Total number of girls after 2 more girls joined the group
= 7 + 2
= 9
New average height after 2 more girls joined the group
= 123 + 8
= 131 cm
Total height of 7 girls
= 7 x 123
= 861 cm
Total height of 9 girls
= 9 x 131
= 1179 cm
Total height of Olivia and Linda
= 1179 - 861
= 318 cm
Answer(s): 318 cm
