Rounding
Round 7,974,284
7,970,000
70 x 50
3,500
524 + 35
559
652 - 491
161
Use partial products to multiply
84 x 36
84 x 36 =
4 x 6 = 24
80 x 6 = 480
30 x 4 = 120
80 x 30 = 2,400
24 + 480 + 120 + 2,400 = 3,024
Estimate 56 x 97
60 x 100 = 6,000
56 x 100= 5,600
62 x 5
310
625,954 + 365,448
991,402
The Delaware River is 301 miles long and the Ohio River is 981 miles long. How much longer is the Ohio river?
981 - 301 =680 miles
Write 80,836 in expanded form
80,000 + 800 + 30 + 6
Estimate 8 x 83
8 x 80 = 640
10 x 80= 800
Carly has 23 students in her World History class. Each has 56 assignments during the year. How many assignments will Carly have to grade?
23 x 56= 1, 288 assignments
A farmer sells 74 apples, 85 peaches, 14 pies, and 45 gallons of cider. How many things did the farmer sell?
74 + 85 + 14+ 45 = 218 items sold
A shepard has 956 sheep. 384 were stolen in the night. How many sheep does the shepard have left?
956 - 384= 572 sheep
Use the distributive property to multiply 5 x 952
5 x 952 = 5 x (900 + 50 + 2)
= (5 x 900) + (5 x 50) + (5 x 2)
= (4,500) + (250) + (10)
=4,760
Using compatible numbers, estimate 73 x 86
70 x 80 = 5,600
70 x 90= 6,300
A train rides 46 miles on Monday and 34 miles on Tuesday. The train rode 4 times the combined distance on Wednesday. How far did the train travel on Wednesday?
46 + 34=80
80 x 4 = 320 miles
Round the numbers, then add
6,254 + 9,324
6,000 + 9,000 =15, 000
95,000 - 65,657
29, 343
Use the partial products to multiply 35 x 23
35 x 23
5 x 3 = 15
30 x 3= 90
20 x 5 = 100
30 x 20= 600
15 + 90 + 100+ 600= 805
Using Compatible numbers, estimate 65 x 24
60 x 25 = 1,500
70 x 20 =1,400
60 x 20= 1, 200
Lisa buys 30 boxes of 24 count colored pencils, and 28 boxes of 12 count crayons. How many coloring tools did she buy?
30 x 24=720 colored pencils
28 x 12=336 crayons
720 + 336=1,056 coloring tools
In May, Joe’s Pizza sold 325 calzones. In June, they sold 429 calzones. How many calzones were sold in total?
325 + 429= 754 calzones
Jon ran 648 miles last year, and 843 miles this year. How many more miles did he run this year than last?
843 - 648 =195 miles
Find the product of 45 x 98
4,410