Fraction.docx

Fraction

Maria spent also spent

of the money her grandparents gave her on an adventure book. She of the money on a bag of candy.

What fraction of the payment has Maria spent? We find the common denominator:

We calculate:

Answer:

Decimal School lunches cost $14.50 per week. About how much would 15.5 weeks of lunches cost? Analysis: We need to estimate the product of $14.50 and 15.5. To do this, we will round one factor up and one factor down. Estimate:

Answer: The cost of 15.5 weeks of school lunches would be about $200. Percentage 24 students in a class took an algebra test. If 18 students passed the test, what percent do not pass? Set up the problem like this: First, find out how many student did not pass. Number of students who did not pass is 24 − 18 = 6 Then, write down the following equation: x% of 24 = 6 or x% times 24 = 6 To get x%, just divide 6 by 24 6/24 = 0.25 = 25/100 = 25% Therefore, 25% of students did not pass Ratio In a group, the ratio of doctors to lawyers is 5:4. If the total number of people in the group is 72, what is the number of lawyers in the group? Solution: Let the number of doctors be 5x and the number of lawyers be 4x. Then 5x+4x = 72 → x=8. Proportion So the number of lawyers in the group is 4*8 = 32. In a mixture of 45 litres, the ratio of sugar solution to salt solution is 1:2. What is the amount of sugar solution to be added if the ratio has to be 2:1? Answer: Number of litres of sugar solution in the mixture = (1/(1+2)) *45 = 15 litres. So, 45-15 = 30 litres of salt solution is present in it. Let the quantity of sugar solution to be added be x litres. Setting up the proportion, sugar solution / salt solution = (15+x)/30 = 2/1 → x = 45. Therefore, 45 litres of sugar solution has to be added to bring it to the ratio 2:1.