Benchmarks
List two fractions that are less than 2/3.
1/3, 2/4, 3/6, etc.
What is the lowest common denominator for 3/5 and 1/2?
LCD = 10
1/4 + 5/16 =
9/16
1 2/5 + 2 3/10
3 7/10
Ms. Storey takes Newt for a walk every day for two weeks. During the first week, Ms. Storey and Newt walk 18 2/3 miles. During the second week, they walk 19 1/5 miles. How many miles did Ms. Storey and Newt walk during the two weeks?
37 13/15 miles
List two fractions that are greater than 2/3.
3/3, 5/6, 11/12 etc.
What is the lowest common denominator for 10/12 and 35/36?
LCD: 36
5/8 - 2/9
29/72
3 5/8 - 1 1/2
2 1/8
Dr. Drake is baking cakes for three customers. The first cake uses 11/14 of a bag of flour. The second cake uses 5/7 of a bag of flour. The third bag uses 3/4 of a bag of flour. If Dr. Drake starts with 3 1/2 bags of flour, how many bags of flour will she have left after making the three cakes?
1/4 of a bag of flour
Is 2/6 or 5/12 closer to one half? How do you know?
5/12. Half would be 6/12 and when 2/6 is multiplied by 2/2 it is 4/12. 5/12 is closer to 6/12 than 4/12.
Find the lowest common denominator and create equivalent fractions with that denominator for the following fractions:
14/18 and 2/3
14/18 and 12/18
4/10 + 9/15
1
1 4/7 + 2 1/2
3 1/14
Ms. Pedroza is wearing a pedometer to track her steps for LEGO league. The first day, Ms. Pedroza walks 15/16 of a mile. The next day, she walks 5/8 of a mile. The third day she walks 1/2 of a mile. Her goal was to walk 1 1/2 in those three days. Did she reach her goal? If she did, how much extra did she walk? If she did not, how much more would she need to walk to reach it?
She walked 2 1/16 miles total. This means, she walked 9/16 of a mile extra.
Is 7/8 or 15/16 closer to 1? How do you know?
15/16. 1 = 16/16. 7/8 = 14/16. 15/16 is closer to 16/16 than 14/16.
Find the LCD and create equivalent fractions with it for the following fractions:
1/9 and 3/5
LCD: 45
5/45 and 27/45
12/13 + 21/39
1 18/39
5 1/6 - 3 2/5
1 23/30
For the Souper Bowl food drive, 5th grade was asked to donate canned food. Each class brought the following:
Mrs. Smith's class: 2 1/3 lbs of soup, 1 3/4 lbs of pasta, and 2 5/12 lbs of sauce.
Mrs. Holle's class: 1 4/6 lbs of soup, 2 10/12 lbs of pasta, and 2 1/2 lbs of sauce.
Which class brought the most food? How much more food did the bring than the other class? How much food was donated all together?
Brought the most food: Mrs. Holle's class
How much more: 1/2 lb
Donated in all: 13 1/2 lbs.
Using benchmark fractions, estimate the answer to the following problem:
5/8 + 12/15 =
5/8 is closest to 1/2. 12/15 is closest to 1. The answer should be about 1 1/2.
Find the LCD and create equivalent fractions with it for the following numbers:
7/12 and 8/10
LCD: 60
35/60 and 48/60
8/9 - 2/7
2/3
2 4/5 + 4 3/4
7 11/20
Mr. Reed is watching football. He watches 1/4 of the game at home. He watches the next 3/8 of the game at Buffalo Wild Wings. Who is his favorite player?
Drew Brees