Estimation
A bakery makes 38 muffins each morning. They bake muffins for 50 mornings in a row. Estimate how many muffins they made in all?
800 (Student answers may vary)
Fill in the blank with the correct symbol:<,=,>.
2/10 _ 12/20
2/10 > 12/20
Solve 40 x 80
3200
Fill in the blank with the correct symbol:<,=,>.
0.90 _ 0.09
0.90 > 0.09
Francis bought 8 packs of glittery pens. Each pack has 30 glittery pens. Francis gives 75 glittery pens away.
Part 1: Create an expression that best represents this problem. Use P to represent the number of glittery pens she has left.
Part 2 : How many glittery pens does she have left?
Part 1: (8 x 30) - 75 = P
P = 165
Part 2: 8 x 30 = 240
240 - 75 = 165
Liam organizes his art supplies into two different storage boxes. One box is for colored pencils. It has 36 sections, and each section holds 14 colored pencils. The other box is for markers. It has 52 sections, and each section holds 9 markers.
Liam’s friend Franklin says Liam has about 10 more colored pencils than markers.
Is Franklin's estimate reasonable? Use estimation to explain.
No, his answer was not reasonable.
Colored Pencils:
36x14
40x14=560
Markers
52x9
52x10=520
Subtract estimation:
560-520=40
Fill in the blank with the correct symbol:<,=,>.
5/6 _ 10/12
5/6 = 10/12
Solve 46 x 32
1472
Fill in the blank with the correct symbol:<,=,>.
0.42_ 0.50
0.42<0.5
Lydia has 12 packs of jelly beans. Each pack has 50 jelly beans. Lydia gives 389 away.
Part 1: Create an expression that best represents this problem. Use J to represent the number of jelly beans she has left.
Part 2 : How many jelly beans does she have left?
Part 1: (12 x 50) - 389 = J
J = 211
Part 2: 12 x 50 = 600
600 - 389 = 211
Iris organizes her sports cards into two binders. One binder is for baseball cards. It has 45 pages, and each page holds 12 cards.The other binder is for basketball cards. It has 58 pages, and each page holds 9 cards.
Iris's brother says she has over 500 more baseball cards than basketball cards. Is his estimate reasonable? Use estimation to explain.
No, her answer was not reasonable.
Baseball Cards:
45x 12
45x10=450
Basketball Cards:
58x9
58x10=580
580-450=130
Fill in the blank with the correct symbol:<,=,>.
58/100 _ 6/10
58/100 < 6/10
Solve 52 x 36.
1872
Fill in the blank with the correct symbol:<,=,>.
.89 _ .98
.89 < .98
Alex is arranging bouquets of flowers. She has two boxes. One for large bouquets and one for small bouquets.
Box for large bouquets: 10 sections, 10 in each section
Box for small bouquets: 20 sections, 30 in each section.
Create an expression to represent this problem. Use a letter to stand for the unknown number. Then, solve to find the unknown number.
(20 x 30) - (10 x 10) = b
600 - 100 = 500
Nora prepares science kits for two projects. For the first project, she fills 39 kits, and each kit needs 17 materials.
For the second project, she fills 48 kits, and each kit needs 12 materials.
Nora thinks she used over 700 more materials for both projects. Is her estimate reasonable? Use estimation to explain.
No, her estimation is not
First project
39x17
39x20=780
Second project
48x12
48x10=480
780+489=1,269
Fill in the blank with the correct symbol:<,=,>.
9/10 _ 91/100
9/10 < 91/100
solve 35 x 25 using standard algorithm
875
Fill in the blank with the correct symbol:<,=,>.
.05 _.005
.05 > .005
Colton works at safeway and is preparing turkeys for thanksgiving. He has two large refrigerators. One for the large turkeys and the other for small turkeys.
Refrigerator for large turkeys: 25 sections, 9 large turkeys in each section
Refrigerator for small turkeys: 50 sections, 18 small turkeys in each section
Create an expression to represent this problem. Use a letter to stand for the unknown number. Then, solve to find the unknown number.
(50 x 18) - (25 x 9) = t
900 - 225 = t
Jayden counts the supplies in two supply carts. The pencil cart has 52 bins, and each bin holds 14 pencils.
The marker cart has 60 bins, and each bin holds 9 markers.
Jayden’s teacher says there are almost 80 more pencils than markers.
Is this estimate reasonable? Use estimation to explain.
Pencil Cart:
52x14
52x10=520
Marker Cart:
60x9
60x10=600
600-520=80
Yes, the teacher's answer was reasonable.
Fill in the blank with the correct symbol:<,=,>.
5/9 _ 2/3
5/9 < 2/3
Solve 372 x 6 using standard algorithm AND partial products
Standard algorithm: 2232
Partial products: 300 x 6 = 1800
70 x 6 = 420 2 x 6 = 12
Fill in the blank with the correct symbol:<,=,>.
0.6 _ 0.60
0.6 = 0.60
Benjamin is filling jugs of lemonade. He has two refrigerators. One for large jugs of lemonade and one for small jugs of lemonade.
Refrigerator for large jugs: 15 sections, 10 large jugs in each section
Refrigerator for small jugs: 35 sections, 40 small jugs in each section
Create an expression to represent this problem. Use a letter to stand for the unknown number. Then, solve to find the unknown number.
(60 x 35) - (35 x 40) = J
2100 - 1400 = 700