Find the standard deviation of the set of sample date 55,53,76,52,91,90(ROUND OFF)

Olivia uses the work below to determine 55% of 720 which explains the error in olivia’s solution

Agrain trader buys the following amounts from three suppliers: 3,200 pounds, 5,100 pounds and 700 pounds. what is the total weight of his purchase?

Aplot of land has been surveyed for a new housing development with borders ab, bc, dc, and da. the plot of land is a right trapezoid with a height of 60 feet and an opposite leg length of 65 feet