The average height of a group of 4 boys is 146 cm. When Mark, Japheth and Ian joined the group, the average height increased by 7 cm. What is Mark, Japheth and Ian's total height?
| |
4 boys |
7 boys |
| Number |
4 |
7 |
| Value |
146 |
153 |
| Total value |
584 |
1071 |
Total number of boys after 3 more boys joined the group
= 4 + 3
= 7
New average height after 3 more boys joined the group
= 146 + 7
= 153 cm
Total height of 4 boys
= 4 x 146
= 584 cm
Total height of 7 boys
= 7 x 153
= 1071 cm
Total height of Mark, Japheth and Ian
= 1071 - 584
= 487 cm
Answer(s): 487 cm
