The average height of a group of 5 girls is 122 cm. When Cathy and Hazel joined the group, the average height increased by 8 cm. What is Cathy and Hazel's total height?
|
5 girls |
7 girls |
Number |
5 |
7 |
Value |
122 |
130 |
Total value |
610 |
910 |
Total number of girls after 2 more girls joined the group
= 5 + 2
= 7
New average height after 2 more girls joined the group
= 122 + 8
= 130 cm
Total height of 5 girls
= 5 x 122
= 610 cm
Total height of 7 girls
= 7 x 130
= 910 cm
Total height of Cathy and Hazel
= 910 - 610
= 300 cm
Answer(s): 300 cm