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Lesson 1 - Estimating Sums



 1. 

Use the number line to select the more reasonable estimate for the sum 24 + 57.
     mc001-1.jpg
a.
30 + 70 = 100
c.
20 + 70 = 90
b.
20 + 60 = 80
d.
40 + 60 = 100
 

 2. 

Use the number line to select the more reasonable estimate for the sum 31 + 72.
mc002-1.jpg
a.
30 + 70 = 100
c.
20 + 70 = 90
b.
40 + 80 = 120
d.
30 + 80 = 110
 

 3. 

Use the number line to select the more reasonable estimate for the sum 46 + 61.
    mc003-1.jpg
a.
40 + 70 = 110
c.
40 + 80 = 120
b.
50 + 80 = 130
d.
50 + 60 = 110
 

 4. 

Use the number line to select the more reasonable estimate for the sum 34 + 79.
    mc004-1.jpg
a.
40 + 80 = 120
c.
30 + 80 = 110
b.
30 + 90 = 120
d.
40 + 90 = 130
 

 5. 

Use the number line to select the more reasonable estimate for the sum 18 + 54.
mc005-1.jpg
a.
10 + 50 = 60
c.
20 + 60 = 80
b.
20 + 50 = 70
d.
20 + 70 = 90
 

 6. 

Aaron has 48 baseball cards in his collection. His sister gives him another 37 cards. About how many cards does Aaron have in total?
a.
40 + 40 = 80; Aaron has about 80 cards.
b.
50 + 30 = 80; Aaron has about 80 cards.
c.
40 + 30 = 70; Aaron has about 70 cards.
d.
50 + 40 = 90; Aaron has about 90 cards.
 

 7. 

Kailee has 63¢ in her wallet. She finds another 28¢ in her coin jar. About how much does Kailee have in total?
a.
60 + 30 = 90; Kailee has about 90¢.
b.
60 + 20 = 80; Kailee has about 80¢.
c.
70 + 30 = 100; Kailee has about $1.00.
d.
70 + 20 = 90; Kailee has about 90¢.
 

 8. 

Yesterday, Ty spent 17 min walking his dog in the morning and 38 min walking his dog after school. About how much time did Ty spend walking his dog yesterday ?
a.
10 + 40 = 50; Ty spent about 50 min walking the dog yesterday.
b.
20 + 50 = 70; Ty spent about 70 min walking the dog yesterday.
c.
10 + 50 = 60; Ty spent about 60 min walking the dog yesterday.
d.
20 + 40 = 60; Ty spent about 60 min walking the dog yesterday.
 

 9. 

Jenn spent $33 on a pair of pants and $42 on a sweater. About how much money did Jenn spend on clothes?
a.
40 + 40 = 80; Jenn spent about $80 on clothes.
b.
30 + 50 = 80; Jenn spent about $80 on clothes.
c.
30 + 40 = 70; Jenn spent about $70 on clothes.
d.
40 + 50 = 90; Jenn spent about $90 on clothes.
 

 10. 

Peter has two containers of orange juice. One contains 73 mL of juice and the other contains 38 mL of juice. About how much orange juice does Peter have in total?
a.
80 + 40 = 120; Peter has about 120 mL.
b.
70 + 40 = 110; Peter has about 110 mL.
c.
70 + 30 = 100; Peter has about 100 mL.
d.
80 + 50 = 130; Peter has about 130 mL.
 



 
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