Answer:
53
Explanation:
The mean is the sum of numbers divided by number of numbers .
We are Given That:
39 + 40 +40 + 41 + 41 + 41 + 41 + 41 + 43 +x divided by 10 = 42
SO, we have to simplify, rearrange and solve for x.
367 + x divided by 10 = 42
367 + x = 420
x = 53.
Hope this helps.
Good Luck