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M4.A.3 Compute accurately and fluently and make reasonable estimates.
M4.A.3.1 Apply rounding and/or estimation strategies to solve
problems.
M4.A.3.1 Eligible Content
• M4.A.3.1.1 Round whole numbers to the nearest ten, hundred, thousand, ten-thousand or hundred-thousand
• M4.A.3.1.2 Round amounts of money to the nearest dollar.
• M4.A.3.1.3 Estimate the answer to addition, subtraction and multiplication problems using whole numbers through 6 digits (for multiplication, no more than 2 digits X 1 digit, excluding powers of 10).
• M4.A.3.1.1 Round whole numbers to the nearest ten, hundred, thousand, ten-thousand or hundred-thousand
• M4.A.3.1.2 Round amounts of money to the nearest dollar.
PSSA Sample Items
Rounding
Use rounding
• When the question asks you
to estimate.• When the question asks
“about how many”…?• When an exact answer isn’t
possible.• When an answer is difficult to obtain.
Memorize this Poem
Find your number.Look right next door.4 or less just ignore.5 or more, add 1
more.
Round this number to the nearestten thousand.
Find your number.3 6 8,9 7
1Circle the number in the ten thousands place.
Round this number to the nearestten thousand.
Look right next door.
3 6 8,9 7 1
Draw an arrow to the right of the number.
Round this number to the nearestten thousand.
4 or less, just ignore.
3 6 8,9 7 1
8 is larger than 4 so go to the nextline of the poem.
Round this number to the nearestten thousand.
5 or more, add 1 more.
3 6 8,9 7 1Add 1 to the 6.
+1
Round this number to the nearestten thousand.
5 or more, add 1 more.
3 7 0,0 0 0Add 1 to the 6 and all the numbers
to the right of the 7 become 0’s.
The Answer
368,971 rounded to the nearest ten thousand is
3 7 0,0 0 0
Round this number to the nearestthousand.
Find your number.
3 5, 3 2 7Circle the number in the thousands
place.
Round this number to the nearestthousand.
Look right next door.
3 5, 3 2 7Draw an arrow to the right of the
number.
Round this number to the nearestthousand.
4 or less, just ignore.
3 5, 3 2 7
Since 3 is less than 4 we do not changethe 5.
Round this number to the nearestthousand.
4 or less, just ignore.
3 5, 0 0 0
Change the numbers to left of 5 to 0’s.
The Answer
35,327 rounded to the nearest thousand is
3 5, 0 0 0
Round this number to the nearestdollar.
Find your number.
$ 5. 8 7
Circle the number where the dollarsare.
Round this number to the nearestdollar.
Look right next door.
$ 5. 8 7
Draw an arrow to the right of thecircled number.
Round this number to the nearestdollar.
4 or less, just ignore.
$ 5. 8 78 is greater than 4 so go to the next
line of the poem.
Round this number to the nearestdollar.
5 or more, add 1 more.
$ 5. 8 7Since 8 is greater than 5 add 1 to the
5.
+1
Round this number to the nearestdollar.
5 or more, add 1 more.
$ 6. 0 0Change the 5 to a 6 and change all the
numbers to the right to 0’s.
The Answer
$5.87 rounded to the
nearest dollar is
$ 6. 0 0
Practice Rounding
Round to the Nearest Hundred
a. 478b. 696c. 233d. 713e. 485f. 778g. 452h. 305i. 841
a. 500b. 700c. 200d. 700e. 500f. 800g. 500h. 300i. 800
Round to the Nearest Thousand
a. 1,715b. 5,475c. 6,562d. 3,470e. 9,025f. 5,789g. 8,543h. 4,007i. 2,800
a. 2,000b. 5,000c. 7,000d. 3,000e. 9,000f. 6,000g. 9,000h. 4,000i. 3,000
Round to the Nearest Ten Thousand
a. 48,253b. 61,744c. 54,769d. 35,535e. 48,600f. 70,209g. 15,437h. 49,036i. 68,703
a. 50,000b. 60,000c. 50,000d. 40,000e. 50,000f. 70,000g. 20,000h. 50,000i. 70,000
Round to the Nearest Hundred Thousand
a. 516,573b. 430,001c. 112,786d. 807,921e. 576,439f. 156,748g. 856,125h. 239,875i. 186,093
a. 500,000b. 400,000c. 100,000d. 800,000e. 600,000f. 200,000g. 900,000h. 200,000i. 200,000
Rounding Money Word Problems
• Mary bought two boxes of crackers for $0.99 each and a pound of grapes for $1.29. About how much did she spend?
• About $3.00
• Martin has 4 quarters and 2 dimes. About how much money does he have?
• $1.00
• At the taco stand, Jaleel bought a taco for $2.75 and a drink for $0.95. About how much did he spend?
• $3.00
• M4.A.3.1.3 Estimate the answer to addition, subtraction and multiplication problems using whole numbers through 6 digits (for multiplication, no more than 2 digits X 1 digit, excluding powers of 10).
PSSA Sample Item
PSSA Sample Item
PSSA Sample Item
Estimating the Answer
• Estimates are not exact numbers. To identify estimates, look for numbers that have been rounded, or look for clues such as almost, over, or about.
Exact Numbers or Estimates?Example
• Mount Rushmore National Memorial, the famous sculpture of 4 American presidents, was started in 1927. It was finished 14 years later and cost almost $1,000,000.00 to make! Mount Rushmore is over 5,500 ft. high. Each head is about 60 ft. tall.
1. In what year was the sculpture started?
2. How tall is each president’s head?
3. How many presidents are on Mount Rushmore?
Refer to the paragraph about Mount Rushmore
4. Is the year 1927 an exact number or an estimate? How do you know?
5. Is it correct to say that the sculpture cost exactly $1,000,000.00 to make? Why or why not?
6. In what year was the sculpture completed? Is your answer an exact answer or an estimate?
7. Why is it important to know if numbers are exact or if they are estimates?
Answer each question. Give a reason for your choice.
Mount Rushmore National Memorial is off Highway 244 and is about 25 miles from Rapid City, South Dakota. The memorial is open 24 hours a day. Each year, more than 2,500,000 people come to view the sculpture.
1. Which number below is used as an estimate?a. 2,500,000 visitors
b. Highway 244
c. 24 hours a day
2. Which number below is used as an exact number?
a. 2,500,000 visitors
b. 25 miles
c. 24 hours a day
3. How many miles is Mount Rushmore from Rapid City?
a. exactly 25 miles
b. about 25 miles
c. 244 miles
Estimate by rounding to the greatest place value
a. 32 + 27 = b. 52 – 37 =c. 86 – 43 =d. 763 – 214 =e. 3,564 + 758 =f. 7,638 + 3,879 =g. 2,375 + 4,680 =h. 24,316 + 13,452 =i. 47,865 + 26, 527 =
a. 60b. 10c. 50d. 600e. 3,000f. 10,000g. 7,000h. 30,000i. 80,000
