Benchmarks
Use benchmarks to estimate 3/8 + 4/5
What is 1/2 + 1= 1 1/2
Jamie is building a bird feeder. He connects two rods together. One rod is 1/6 and the other rod is 2/3. What is the total length of the rods?
What is 5/6
What is 2 3/5 + 1 3/10?
What is 4 1/3- 2 5/6?
What is 1 9/18
The Foster's spend 5 1/2 hours at the pier. They spend 1 1/3 hours eating and the rest of the time walking the boardwalk. Write an equation to find t, the amount of time they spent walking the boardwalk.
What is 5 1/2- 1 1/3= t
Use benchmarks to estimate 1/10 + 5/8
What is 0 + 1/2= 1/2
What is 3/4- 1/8?
What is 5/8
What is 3 7/8- 1 1/2?
Marcus has a board that is 7 1/4 feet long. He cuts off a piece that is 2 1/2 feet long. How long will the board be?
What is 7 1/4- 2 1/2= 4 3/4
Nelly watched two movies on Saturday. The second movie lasted 2 3/4 hours. He spent 5 1/3 hours watching both movies. How long was the first movie? Write an equation, and solve
Equation- m+ 2 3/4= 5 1/3 or 5 1/3- 2 3/4= m
Solve- 2 7/12
Use benchmarks to estimate 10/12- 3/6
what is 1- 1/2= 1/2
What is 2/8 + 11/16?
What is 15/16
Caroline trains every weekend for a track competition. She runs sprints for 2 2/5 hours and hurdles for 1 1/4 hours. How many hours does she spend training?
What is 2 2/5+ 1 1/4= 3 13/20
What is 5 1/4- 1 1/3?
What is 3 11/12
Lexi takes photos of food for magazines. At a photoshoot, she spends 5/6 hours arranging food and 1 3/4 hours taking photos of the food. Write an equation to model the number of hours Lexi spends at the photoshoot. How many hours is she there for?
What is 5/6 + 1 3/4= h
She spends 2 7/12 hours at the photoshoot.
Use benchmarks to estimate 1/4+ 1/8
What is 0+ 0= 0
OR
1/2+0= 1/2
Mr. Smith's laptop memory is 9/10 full. After he deletes some files, the memory is 3/5 full. How much memory does Mr. Smith delete?
What is 3/10
Sarah buys a bag of apples that weighs 2 7/16 pounds and another bag that weighs 2 1/2 pounds. What is the total weight?
What is 4 15/16
Franco practices the piano for 4 1/2 hours each week. He plays soccer for 1 3/4 hours. How much longer does Franco practice piano than play soccer?
What is 2 6/8
Lauren measures 2 1/4 cup of flour for a recipe. She then realizes that she needs to add 2/3 cup of flour. Does Lauren use more or less than 3 cups of flour? Explain
Less than 3 cups because Lauren uses 2 11/12 cups of flour which is less than 3 cups.
Use benchmarks to estimate 2/8- 1/3
What is 0-0
OR
1/2- 0= 1/2
Tracy checks the digital tablets made at a factory. In one box of tablets, she finds that 1/20 have a cracked screen. In the same box, she finds that another 1/5 have the wrong software. What fraction of the tablets in the box have either a cracked screen or the wrong software?
What is 5/20
Ed buys a plant that will grow to be 8 1/2 inches tall. The plant Ed buys today is 3 3/8 inches tall. How many more inches is the plant expected to grow?
What is 8 4/8- 3 3/8= 5 1/8
Hannah grows two corn plants. The first plant is 6 1/4 feet tall. The second plant is 4 6/8 feet tall. How much taller is the first corn plant than the second corn plant?
What is 1 16/32 feet
One balloon is 3 7/10 meters above the ground. A second balloon is 2 3/5 meters higher. How far above the ground is the second balloon? Write an equation, estimate, solve it, and explain if your answer is reasonable.
Equation- 3 7/10+ 2 3/5= b
Estimate- 4+ 2 1/2= 6 1/2
Solve- 6 3/10
Reasonable- Yes because my answer is close to my estimate.