Answer: 14
Step-by-step explanation:
We arrange the number as -3, 1, 7, 8, 18, 19, 42, the old median is 8.
But the median has change to 11 when the number is add, which means that the number is between 7 and 18.
(8 + x)/2 = 11 Where x is the new number
8 + x = 22
x = 14
