Question

The average temperature for Wednesday, Thursday and Friday was ${40}^{\circ }\text{C}$ and for Thursday, Friday and Saturday was ${41}^{\circ }\text{C}.$ If temperature on Saturday was ${42}^{\circ }\text{C},$ then what was the temperature on Wednesday?

• A. ${39}^{\circ }\text{C}$
• B. ${44}^{\circ }\text{C}$
• C. ${38}^{\circ }\text{C}$
• D. ${41}^{\circ }\text{C}$

Answer 1

The correct option is A ${39}^{\circ }\text{C}$

Average temperature for Wednesday, Thursday and Friday $={40}^{\circ }\text{C}.$
$\therefore$ Total temperature of three days $=40\times 3={120}^{\circ }\text{C}$
$\Rightarrow$ Wednesday $+$ Thursday $+$ Friday $={120}^{\circ }\text{C}\cdots \left(1\right)$

Average temperature for Thursday, Friday and Saturday $={41}^{\circ }\text{C}.$
$\therefore$ Total temperature of three days$=41\times 3={123}^{\circ }\text{C}$
$\Rightarrow$ Thursday $+$ Friday $+$ Saturday $={123}^{\circ }\text{C}\cdots \left(2\right)$

Subtracting $\left(1\right)$ and $\left(2\right),$ we get
Saturday $-$ Wednesday $=3$
$\Rightarrow$ Wednesday $=42-3={39}^{\circ }\text{C}$
($\because$ Temperature on Saturday $={42}^{\circ }\text{C}$)