The average temperature for Monday, Tuesday, Wednesday and Thursday was 48 degrees and for Tuesday, Wednesday, Thursday and Friday was 46 degrees. If the temperature on Monday was 42 degrees. Find the temperature on Friday?

40 degrees

36 degrees

34 degrees

None of these

Let's denote the temperatures:

M = Monday = 42 degrees

T = Tuesday

W = Wednesday

Th = Thursday

F = Friday

Given:

(M + T + W + Th) / 4 = 48

M + T + W + Th = 192

42 + T + W + Th = 192

T + W + Th = 150 ... (1)

(T + W + Th + F) / 4 = 46

T + W + Th + F = 184 ... (2)

Subtract (1) from (2):

(T + W + Th + F) - (T + W + Th) = 184 - 150

F = 34

The temperature on Friday was 34 degrees.