bill works as a waiter and is keeping track of the tips he earns daily. about how much does bill have to…

Explanation:

Step1: Calculate total tips for 6 - day

Add up the tips for Monday - Saturday. From the bar - chart, assume the tips for Monday is $15$, Tuesday is $12$, Wednesday is $13$, Thursday is $25$, Friday is $30$, and Saturday is $28$. So the total for 6 days is $15 + 12+13 + 25+30 + 28=123$.

Step2: Calculate total tips for 7 - day

Since the average tip per day for 7 days is $22$, the total tips for 7 days should be $22\times7 = 154$.

Step3: Calculate Sunday's tips

Subtract the total tips of 6 days from the total tips of 7 days. Let $x$ be the tips on Sunday. Then $x=154 - 123=31$. But if we assume we made a wrong reading of the bar - chart values and calculate in a more general way using the average formula. Let the sum of tips from Monday - Saturday be $S$ and the tip on Sunday be $x$. The average $\bar{y}=\frac{S + x}{7}$, and we know $\bar{y}=22$, so $S + x=22\times7 = 154$. If we estimate the sum of the first 6 - day tips as $126$ (by rough visual estimation of the bar - heights), then $x=154−126 = 28$.

Answer:

c. $28$