Place Value and Estimation
Round the factors to estimate the products.
597 x 52 ~ _____ x ______ = ______
A reasonable estimate for 597 x 52 is _________
Answer:
597 x 52 ~ 600 x 50 = 30,000
A reasonable estimate for 597 x 52 is 30,000
Write the expression and the value of the expression.
50 times the difference of 64 and 36
Answer:
Expression: 50 x (64-36) =
Value of the Expression: 1,400
Compare the two expressions using >, <, or =. For each, explain how you can determine the answer without calculating.
100 x 8 ____ 25 x (4x8)
Answer:
100 x 8 = 25 x (4x8)
I used the associative property and knew that 25 x 4 is equal to 100 and 100 x 8 is 800
Solve:
For a field trip, the school bought 45 sandwiches for $6.60 each and 38 bags of chips for $1.25 each. How much did the school spend in all?
Answer:
45 x $6.60= 297.00
38 x $1.25= 47.50
297.00+47.50=$344.50
The school spent $344.50 in all.
Determine if these equations are True or False.
44x20x10 = 440x2
False
44x20x10 = 8,800
440x2 = 880
Write the expression and the value of the expression.
Divide the sum between 800 and 700 by 5
Answer:
Expression: (800+700) / 5
Value of the Expression: 300
Compare the two expressions using >, <, or =. For each, explain how you can determine the answer without calculating.
48 x 12 ____ 60 twelves - 13 twelves
Answer:
48 x 12 < 60 twelves - 13 twelves
I knew this because 48 is less than 60 twelves and 12 is less than 13 twelves.
Jeanne makes hair bows to sell at the craft fair. Each bow requires .5 yards of ribbon.
At the fabric store, ribbon is sold by the foot. If Jeanne wants to make 84 bows, how many feet of ribbon must she buy?
Answer:
0.5 yard = 0.5 x (1 yard)
= 0.5 x (3 feet)
= 1.5 feet
15 tenths x 84 = 1260 tenths = 126.0
Jeanne has to buy 126 feet of ribbon.
Fill in the blanks using your knowledge of place value units and basic facts.
23x20
Think: 23 ones x 2 tens = ___________ tens
23x20= ____________
Answer:
23 ones x 2 tens = 46 tens
23x20 = 460
Write the expression and the value of the expression.
The sum of 4 thirteens and 16 thirteens
Answer:
Expression: (13x4) + (16x4) =
Value of the Expression: 116
Compare the two expressions using >, <, or =. For each, explain how you can determine the answer without calculating.
24 x 36 ____ 18 twenty-fours, tripled
Answer:
24 x 36 < 18 twenty-fours, tripled
I knew this because there was only 1 twenty-four in the first problem.
MUST HAVE ANSWER TO 'WORD PROBLEMS 200' BEFORE COMPLETING THIS QUESTION
If the ribbon costs 10cents per foot, what is the total cost of the ribbon in dollars? Explain your reasoning including how you decided where to place the decimal.
Answer:
126 x 10cents = 1260cents
1260cents = $12.60
I put 2 decimal places because 10cents in written for is 0.10. To change to dollars, there must be two digits after the decimal for the answer.
Fill in the blanks using your knowledge of place value units and basic facts.
3,310x300
_____ tens x _____ hundreds = 993 _______
3,310x300= _________
Answer:
331 tens x 3 hundreds = 993 thousands
3,310x300= 993,000
Write the expression and the value of the expression.
12 times the sum of 6 and 12
Answer:
Expression: 12 x (6+12) =
Value of the Expression: 216
Solve. Use words, numbers, or pictures to explain how your answers to both parts, are related.
a. 45x30=
b. 4.5x30=_________tenths x 30=_____________
Answer:
a. 45x30= 1,350
b. 4.5x30= 45 tenths x 30 = 135
I knew they were related because the factors are the same for both parts, just different place values
MUST HAVE ANSWER TO 'WORD PROBLEMS 200' BEFORE COMPLETING THIS QUESTION
A manufacturer is making 1,000 times as many bows as Jeanne to sell in stores nationwide. Write an expression using exponents to show how many yards of ribbon the manufacturer will need. Do not calculate the total.
Answer:
42 x 103
OR
84 x 103 x 0.5
Find the product. Show your thinking.
7x9=
7x90=
70x90=
70x900=
7X9
=63
7X90
=63x10
=630
70X90
=(7x10)x(9x10)
=(7x9)x100
=6,300
70X900
=(7x9)x(10x100)
=63,000
Write the words and the value of the expression.
11 x (24 + 45)
Answer:
Words: 11 times the sum of 24 and 25
Value of the Expression: 759
Solve. Use words, numbers, or pictures to explain how your answers to both parts, are related.
a. 95x70=
b. 9.5x70=_________tenths x 70=_____________
Answer:
a. 95x70= 6,650
b. 9.5x70= 95 tenths x 70 = 665
I knew they were related because the factors are the same for both parts, just different place values
Michael makes hair bows to sell at the craft fair. Each bow requires 1.5 yards of ribbon.
At the fabric store, ribbon is sold by the foot. If Michael wants to make 84 bows, how many feet of ribbon must he buy?
Answer:
1.5 yard = 1.5 x (1 yard)
= 1.5 x (3 feet)
= 4.5 feet
45 tenths x 84 = 3780 tenths = 378.0
Michael has to buy 378 feet of ribbon.