Question

The mean of 19 students is 126cm.

Another student joins the group and the mean becomes 128cm.
What is the height of the new student?

Answer 1

Answer: 166 cm

Explanation:

x / 19 = 126

* 19 * 19

x = 2394

(2394 + y) / 20 = 128

* 20 * 20

2394 + y = 2560

- 2394 - 2394

y = 166