Mental Math
Estimate the product of the following expression.
34 x 286
30 x 300 = 9,000
What is the product of the following equation?
23 x 4
92
Write the expression in number form.
50 times the sum of 64 and 36
50 x (64 + 36)
Lucas bought 13 ping-pong balls for 75 cents each. How much did he pay in total for the ping-pong balls?
Lucas paid $9.75 for the ping-pong balls.
Convert 8 weeks to days.
1 week = 7 days.
56 days
Estimate the product of the following expression.
35 x (24 + 36)
40 x ( 20 + 40) = 40 x 60 = 2,400
32.456 x 4.76 = 15449056
154.49056
Write the expression in number form.
The sum of 12 sixteens and 3 fives.
(12 x 16) + (3 x 5)
Explain what are the three steps for solving this problem. Do not solve!
For a field trip, the school bought 47 sandwiches for $4.60 each and 39 bags of chips for $1.25 each. How much did the school spend in all?
The second step is to multiply 39 x $1.25.
The third step is to add the two products.
Convert 9.2 meters to centimeters.
1 meter = 100 centimeters.
920 centimeters
Use mental math to explain if the expression is < , >, =.
24 x 36 ___ 18 twenty-fours, doubled
The two expression are equal because 18 doubled is 36. Both expressions are 24 x 36.
What is the product of the following equation?
34 x 57
1,938
Write the expression in number form and SOLVE.
The difference of 3 eights and 2 sixes.
(3 x 8) - (2 x 6) = 12
Frida bought 36 feet of ribbon for an art project. If the ribbon costs 10¢ per foot, what is the total cost of the ribbon in dollars? Explain your reasoning, including how you decided where to place the decimal.
Convert 6.08 kilograms to grams.
1 kilogram = 1,000 grams
6,080 grams.
Use mental math to explain if the expression is < , >, =.
24 x (20 + 5) ____ (20 + 5) x 12
The first expression is > than the second expression because it is 25 x 24 and the second expression is 25 x 12. 24 is greater than 12.
What is the product of the following equation?
4.6 x 23
111.8
Write the numerical expression in word form.
5 x (17 - 7)
Five times the difference of 17 and 7.
Solve the following.
For a class party, Ms. Jacqueline bought 16 cookies for $2.35 each and 8 bags of chips for $1.12 each. How much did Ms. Jacqueline spend in all?
Ms. Jacqueline spent $46.56 total.
Convert 14.5 pounds to ounces.
1 pound = 16 ounces
232 ounces.
Use mental math to explain if the expression is < , >, =.
18 x 27 ___ 20 twenty-sevens minus twenty-seven
The first expression is < than the second expression because 20 twenty-sevens minus twenty-seven is 19 twenty-sevens. 18 is less than 19.
What is the product of the following equation?
89.6 x .33
29.568
Write the numerical expression in word form and SOLVE.
(3 x 15) + (2 x 10)
The sum of 3 fifteens and 2 tens.
65
Luna makes Christmas bows to sell at the Christmas fair. Each bow requires 3.5 yards of ribbon.
At the fabric store, ribbon is sold by the foot (1 yard = 3 feet). If Luna wants to make 84 bows, how many feet of ribbon must she buy? Show all your work.
Luna would need to buy 882 feet of ribbon.
Liza’s cat had six kittens! When Liza and her brother weighed all the kittens together, they weighed 4 pounds 2 ounces. Since all the kittens are about the same size, about how many ounces does each kitten weigh?
Each kitten weighs 11 ounces.