A perfect square is a number made up by 2 exact identical numbers multiplying each other, and a perfect cube is the same but 3 exact identical numbers.
The first perfect cube is 1, as 1 x 1 x 1 = 1.
Perfect square : 1,4,9,16,25,36,49,64,...
So, the 7th perfect square is 49.
Sum of 1st perfect cube and 7th perfect square is 1 + 49 = 50.