The average temperature for Monday, Wednesday and Friday was $ 41^\circ$C. The average for Wednesday, Friday and Thursday was $ 42^\circ$C. If the temperature on Thursday was $ 43^\circ$C, then the temperature on Monday was:
Answer & explanation
Correct answer: option 4
Sum of temp. of monday, wednesday and friday = 41 x 3 = 123° C
Sum of temp. of wednesday, friday and thursday = 42 x 3 = 126° C
Temp. on thursday = 43° C
Temp. on wednesday and friday = 126 - 43 = 83° C
Temp. on monday = 123 - 83 = 40° C