Question

The average temperature of the first three days of a week is ${27}^{\circ }C$ and the next three days is ${29}^{\circ }C$. If the weekly average is ${28.5}^{\circ }C$, What is the temperature on the last day?

• A. ${31.5}^{\circ }C$
• B. ${28}^{\circ }C$
• C. ${21}^{\circ }C$
• D. ${42}^{\circ }C$

Answer 1

Answer: (A)

${31.5}^{\circ }C$

$28.5\times 7-27\times 3-29\times 3={31.5}^{\circ }C$