Here are the step-by-step solutions for each problem. To estimate, we round each number to the nearest hundred and then add or subtract.
1) Walnut trees
* Round 4,162 to
4,200.
* Round 6,786 to
6,800.
* Add them together: $4,200 + 6,800 = 11,000$.
2) Video game points
* Round 6,776 to
6,800.
* Round 2,372 to
2,400.
* Add them together: $6,800 + 2,400 = 9,200$.
3) Pokemon cards
* Round 6,526 to
6,500.
* Round 4,156 to
4,200.
* Subtract (since she gave some away): $6,500 - 4,200 = 2,300$.
4) Limes picked
* Round 4,566 to
4,600.
* Round 5,155 to
5,200.
* Add them together: $4,600 + 5,200 = 9,800$.
5) Quarters in bank
* Round 7,644 to
7,600.
* Round 2,257 to
2,300.
* Subtract (since he spent them): $7,600 - 2,300 = 5,300$.
6) Marbles collected
* Round 9,114 to
9,100.
* Round 3,821 to
3,800.
* Add them together: $9,100 + 3,800 = 12,900$.
7) Books owned
* Round 1,699 to
1,700.
* Round 3,835 to
3,800.
* Add them together: $1,700 + 3,800 = 5,500$.
8) Domestic letters
* Round 9,618 to
9,600 (total letters).
* Round 2,193 to
2,200 (foreign letters).
* Subtract foreign from total to find domestic: $9,600 - 2,200 = 7,400$.
9) Pages unread
* Round 7,574 to
7,600 (total pages).
* Round 1,433 to
1,400 (pages read).
* Subtract read from total to find unread: $7,600 - 1,400 = 6,200$.
10) Doughnut boxes sold by others
* Round 6,517 to
6,500 (total boxes).
* Round 3,294 to
3,300 (Sally's boxes).
* Subtract Sally's sales from the total: $6,500 - 3,300 = 3,200$.
Final Answer:
1) 11,000
2) 9,200
3) 2,300
4) 9,800
5) 5,300
6) 12,900
7) 5,500
8) 7,400
9) 6,200
10) 3,200
Parent Tip: Review the logic above to help your child master the concept of estimation maths worksheet.
