This Math quiz is called 'Rates and Ratios' and it has been written by teachers to help you if you are studying the subject at middle school. Playing educational quizzes is a fabulous way to learn if you are in the 6th, 7th or 8th grade - aged 11 to 14.
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A rate is a special ratio because it is a comparison of measurements that have different units such as dollars and cents or pounds and ounces. A unit rate is a rate with a denominator of 1.
Let’s look at the following example:
Betty is buying jellybeans for her sister’s birthday party. She buys a bag of 10 lbs. of jellybeans that costs $45.00. Betty is wondering how much 1 lb. of jellybeans cost.
First, we convert $45.00 to cents by moving the decimal point two spaces to the right. $45.00 = 4500 cents.
We now create a fraction using the cents with the pounds of jellybeans. In this case we have 10 lbs. of jellybeans so our fraction will be 4500/10 lbs. We now need to divide the denominator with the numerator so 4500 ÷ 10 = 450. Since we divided the numerator by10 we must do the same with the denominator so 10 ÷ 10 = 1. Now our fraction is 450/1 which is a unit rate. 450/1 = 450. Now we convert back to dollars by adding our decimal back in by placing it two spaces to the left or 4.50. This tells us that 1 lb. of jellybeans cost $4.50. $4.50 is the rate.