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Vocabulary!
Estimating Sums
Estimating Differences
Word Problems
100
Define this math word: SUM
The SUM is the answer to an addition problem. Example: Find the Sum of 13 and 19
100
Round to the nearest 10 and find the SUM 32 and 29
60! 32 rounds down to 30. 29 rounds up to 30. 30 plus 30 is 60!
100
Round to the nearest hundred and find the DIFFERENCE: 311 and 205
100! 311 rounds down to 300. 205 rounds down to 200. The Difference between 300 and 200 is 100. (Can you solve that in your head too??)
100
In the month of August, Third grade students earned 537 bear bucks for great behavior. Round to the nearest 10. About how many bear bucks did these students earn?
The students earned ABOUT 540 bear bucks.
200
Define this math term: DIFFERENCE
The DIFFERENCE is the answer to a subtraction problem. Example: Find the DIFFERENCE between 59 and 42
200
Round to the nearest 10 and find the sum: 45 and 83
130! 45 rounds up to 50 83 rounds down to 80 80+50= 130
200
Round to the nearest 10 and find the DIFFERENCE: 72 and 36
30! 72 rounds down to 70. 36 rounds up to 40. The difference between 70 and 40 is 30! (can you compute that mentally, too?)
200
Ms. Thomas made Mr. Witzeman 784 cookies. (He loves cookies...). About how many cookies did she make?
Ms. Thomas made ABOUT 800 cookies. Or, about 790 cookies. Both are good ESTIMATES. Why would it be OK to use either?
300
Define this term: ROUNDING
ROUNDING is a process where you find about how much or about how many by picking the nearest 10 or 100 to the real number. EXAMPLES: 45 rounded to the nearest 10 is 50! 462 rounded to the nearest 10 is 460. 462 rounded to the nearest hundred is 500. REMEMBER: 4 to the floor, 5 climb the vine!
300
Round each addened to the nearest 100 and find the sum 634 and 159
800! 634 rounds down to 600. 159 rounds up to 200. 200+600=800
300
Round to the nearest ten and find the DIFFERENCE: 56 and 88
30! 88 rounds up to 90. 56 rounds up to 60. 90-60=30
300
Study the following Chart: About how many bear bucks did Duke earn? Round to the nearest 10.
350!
400
Define this math term: ESTIMATE
ESTIMATE means to find ABOUT how much or ABOUT how many. You can ESTIMATE by ROUNDING! The two words are very similar!
400
Round to the nearest 10 and find the sum: 135+ 233
370! 135 rounds up to 140. 233 rounds down to 230. 230+140=370 (watch how I use BREAK APART!)
400
Round to the nearest 10 and find the DIFFERENCE: 152 and 110
40! 152 rounds down to 150. 110 rounds to...110 (it already IS the nearest 10) 150-110= 40 (heres how I would solve it in my head)
400
What is the best estimate for how many bear bucks Virginia Tech and Wake Forrest earned in all? a. 300 b. 400 c. 450 d. 600
450!
500
DAILY DOUBLE! First team to solve this problem gets 500 points! Ms. Dalton has 387 dollars. Ms. Bennett has 221 dollars. Find the sum of their money.
608! Watch how I do it and check your work with me...
500
Round to the nearest 10 and find the sum: 59 225
290! 59 rounds up to 60. 225 rounds up to 230. 230 plus 60 is 290. Phew...that was a little tough.
500
Round to the nearest ten and find the DIFFERENCE: 85 and 163
70! 163 rounds down to 160 85 rounds up to 90 160-90=70
500
About how many bear bucks did the third grade earn in all? First team to round to the nearest 100 and find the sum wins the points!!
They earned ABOUT 1,500 BEAR BUCKS! WOW! Watch how I do it...