In Small Town, Iowa the annual income for four families are as follows. Find the mean and median of these incomes.
| $45,687 | $68,900 | $29,450 | $53,963 |
Mean: The mean is the average, found by adding all the terms together and then dividing by the number of terms.
Add: 45,687 + 68,900 + 29,450 + 53,963 = 198,000
Divide: 198,000 ÷ 4 = 49,500
The mean income for these families is $49,500.
Median: The median is the middle term, found by listing the numbers in order from least to greatest and selecting the number in the middle. If there are two numbers in the middle, find the average of these two.
| List the numbers: | $29,450 | $45,687 | $53,963 | $68,900 |
| Locate the middle: | $29,450 | $45,687 | $53,963 | $68,900 |
Find the average of these two middle numbers:
(45,687 + 53,963) ÷ 2 = 49,825
The median income is $49,825.
Marcia earns $2,050 a month at her job at FoodSource. How much is her average weekly income?
To find Marcia’s weekly income, we need to know that there are 4 weeks in a month. To find the average, we must divide the monthly income by 4.
2050 ÷ 4 = 512.50
Therefore, Marcia earns an average of $512.50 per week.
At their lemonade stand, Alex and Dylan sell 134 glasses of lemonade at $0.50 each. How much does each kid earn?
First we need to determine the total amount earned on the lemonade sales. To do this, we multiply the number of glasses sold by the price for each glass:
134 x $0.50 = $67
Now we can divide the total profit by 2 since there were two people selling the lemonade:
67 ÷ 2 = 33.50
Alex and Dylan each earned $33.50.
Sam and Paul were both running for class president. Sam got 475 votes, and Paul got 310. How many people voted, and what percent of the vote did Sam and Paul each get?
To get the total votes, we can add the number of votes that Sam and Paul got:
475 + 310 = 785 votes
To get the percent of votes that Sam and Paul got, divide their personal totals by the total number of votes, and then change these values to a percentage:
Sam: 475 ÷ 785 = 0.605 = 60.5%
Paul: 310 ÷ 785 = 0.395 = 39.5%
Mona wants to buy a car. How much interest will she pay on a loan for $5,000 at 3% interest over 2 years?
To solve this problem, you need to know this basic formula:
- Interest = Principal x Rate x Time
- Principal is the $$ amount.
- Rate is the percent of interest being charged, written as a decimal.
- Time is always expressed in years.
Just plug the given values into the equation:
I = P x R x T
I = 5,000 x 0.03 x 2
I = $300
Mona will pay $300 in interest over two years.