Find the output, y, when the input, x, is -1

Will give brainliest sum of arithmetic series (sigma notation) find the numerical answer to the summation given below. (image shown below)

Noor brought 21 sheets of stickers. she gave 1/3 of a sheet to each of the 45 students at recess. she wants to give teachers 1 1/2 sheets each.

How many kilometers are equal to 5 miles? use 1 mile ≈ 1.61 kilometers. !