Estimating & Rounding
Show on a number line:
Is 548 between 500 and 600.
548 is closer to 550.
Number line should show 500 until 600.
482 + 397 = ?
482 + 397 = 879
7 x 4
7 groups with 4 in all which should give you 28
At Fernando's school party, the children make teams of 5 to play a game. If there are 35 children? How many teams are there?
7 teams
Each pack has 6 pencils. The teacher buys 8 packs and already has 15 pencils. How many pencils are there in all?
Which of the following numbers round to 300 when rounding to the nearest hundred?
A. 238
B. 250
C. 283
D. 342
E. 359
B. 250
C. 283
D. 342
Kyle's basketball team scores 62 points. Kyle's team members score 51 of the points, Kyle scores the rest of the points. How many points does Kyle score?
Kyle scores 11 points.
Use repeated addition to solve this problem:
There are 6 jars of pickles in a box. Ed has 3 boxes of pickles. How many jars of pickles does he have?
6 + 6 + 6 = 18 jars
Use repeated subtraction to solve:
Marquis has 30 grapes. He keeps 9 grapes to himself. Then, he gives 7 grapes each to some of his friends, To how many friends does Marquis give grapes?
3 friends
There are 24 cookies shared equally among 6 students. After sharing, the teacher brings 10 more cookies.
How many cookies are there now?
34 cookies
Use rounding to estimate the sum to the nearest tens and then again using the nearest hundreds.
327 + 581
327 + 581 --> 330 + 580 = 910
and
327 + 581 --> 300 + 600 = 900
A pet shelter has 16 dogs, 30 cats, and 24 birds, How many animals are at the pet shelter in all?
70 animals
Use a MULTIPLICATION bar model to solve.
Roberto put some toy blocks into 3 rows. There are 5 blocks in each row. How many blocks are there?
There should be a large box with 3 groups of 5 showing a total of 15.
Make an array to show the division equation:
32 / 8 = ?
should gave 8 rows or 8 columns with 4 in each.
The teacher has 36 crayons and puts them into 9 boxes equally. Later, she adds 2 more crayons to each box.
How many crayons are there in total now?
54 total
Which of the following equations show the Commutative Property of Addition:
A. 27 + 4 = 31
B. 27 + 4 = 4 + 27
C. 27 + 0 = 0 + 27
D. 27 + (4 + 0) = (27 + 4) + 0
B and C
B. 27 + 4 = 4 + 27
C. 27 + 0 = 0 + 27
Write the name of the property that you can use to find the sum of: 22 + 0
Identity Property of Addition
How many different types of fabric are there?
6 x 5 = 30
4 x 4 = 16
= 46 fabrics
Mr Martin buys 36 muffins for a class breakfast. He places them on plates for his students. If he places 9 muffins on each plate, ow many plates does Mr Martin use?
4 plates
A class has 7 groups. Each group has 6 students. Each student brings 1 water bottle. After lunch, 9 bottles are thrown away.
How many water bottles are left?
7 x 6 = 42
42 x 1 (Each bottle) = 42
9 bottles thrown away 42-9 = 33 bottles.
Write each number sentence below the better estimate of the sum... 400 or 500?
A. 236 + 189 = ?
B. 305 + 72 = ?
C. 195 + 238 = ?
D. 215 + 289 = ?
400: B. 305 + 72 = ? and C. 195 + 238 = ?
500: A. 236 + 189 = ? and D. 215 + 289 = ?
Jenna buys 2 bags of dog food for her dogs. One bag weighs 37 pounds. The other bag weights 15 points. How many pounds do both bags weigh? Explain how you solved the problem!
52 pounds.
Ken watches as marching band. He sees 2 rows of flute players. Six people are in each row. He sees 8 trombone players. How many flute players and trombone players does Ken see?
20 flute players and trombone players.
Use a number line to show the division problem:
Sam visited his cousins for 49 days over the summer. There are 7 days in each week. How long, in weeks, was Sam visiting?
7 weeks. Number line should show 0 - 49 with 7 jumps of 7.
There are 48 markers shared equally among 8 tables. Each table already has 3 markers.
How many markers does each table have now?
Share the markers equally:
48 ÷ 8 = 6 markers at each table
Add the markers already at each table:
6 + 3 = 9 markers
✅ Each table has 9 markers now.