The average height of a group of 6 boys is 150 cm. When Billy, Henry and Albert joined the group, the average height increased by 4 cm. What is Billy, Henry and Albert's total height?
| |
6 boys |
9 boys |
| Number |
6 |
9 |
| Value |
150 |
154 |
| Total value |
900 |
1386 |
Total number of boys after 3 more boys joined the group
= 6 + 3
= 9
New average height after 3 more boys joined the group
= 150 + 4
= 154 cm
Total height of 6 boys
= 6 x 150
= 900 cm
Total height of 9 boys
= 9 x 154
= 1386 cm
Total height of Billy, Henry and Albert
= 1386 - 900
= 486 cm
Answer(s): 486 cm
