The average height of a group of 9 girls is 131 cm. When Kylie and Shiyun left the group, the average height decreased by 7 cm. What is Kylie and Shiyun's total height?
|
9 girls |
7 girls |
Number |
9 |
7 |
Value |
131 |
124 |
Total value |
1179 |
868 |
Total number of girls after 2 girls left the group
= 9 - 2
= 7
New average height after 2 girls left the group
= 131 - 7
= 124 cm
Total height of 9 girls
= 9 x 131
= 1179 cm
Total height of 7 girls
= 7 x 124
= 868 cm
Total height of Kylie and Shiyun
= 1179 - 868
= 311 cm
Answer(s): 311 cm