Question

Directions: Estimate the sum or difference using front end estimation.

1) 97 – 39

2) 812,344 – 187,675

3) 321 + 79

Directions: Estimate the product using front end estimation.

4) 315 x 821

5) 562 x 791

6) 82 x 156

7) 711 x 884

8) 126 x 952

9) 824 x 541

10) 4027 x 78

11) 796 x 123

Directions: Estimate the quotient using front end estimation.

12) 817 19

13) 3615 72

14) 232 64

15) 559 81

16) 2986 222

17) 10275 232

18) 7428 286

19) 7143 369

20) 628,597 1525

Answer 1

1) 100 - 40 = 60

2) 800000 - 200000 = 600000

3) 300 + 80 = 410

4) 3000 + 800 = 1100

5) 600× 800 = 480000

6) 80×200 = 16000

7) 700×900 = 630000

8) 100×1000 = 100000

9) 800× 500 = 400000

10) 4000×80 = 320000

11) 800×100 = 80000

12) 800/20 = 40

13) 4000/70 = 57.1 = 60

14) 200/60 = 33.3 = 30

15) 600/80 = 7.5 = 8

16) 3000/200 = 15

17) 10000/200 = 50

18) 7000/300 = 23.3 = 20

19) 7000/400 = 17.5 = 18

20) 600000 / 2000 = 300

Explanation:

1) 1) 97 – 39. It becomes

100 - 40 = 60

2)2) 812,344 – 187,675. It becomes

800000 - 200000 = 600000

3)321 + 79. It becomes

300 + 80 = 410

4) 315 x 821. It becomes

300 + 800 = 1100

5) 562 x 791. It becomes

600× 800 = 480000

6) 82 x 156. It becomes

80×200 = 16000

7) 711 x 884. It becomes

700×900 = 630000

8) 126 x 952. It becomes

100×1000 = 100000

9) 824 x 541. It becomes

800× 500 = 400000

10) 4027 x 78. It becomes

4000×80 = 320000

11) 796 x 123. It becomes

800×100 = 80000

12) 817 19. It becomes

800/20 = 40

13) 3615 72. It becomes

4000/70 = 57.1 = 60

14) 232 64. It becomes

200/60 = 33.3 = 30

15) 559 81. It becomes

600/80 = 7.5 = 8

16) 2986 222. It becomes

3000/200 = 15

17) 10275 232. It becomes

10000/200 = 50

18) 7428 286. It becomes

7000/300 = 23.3 = 20

19) 7143 369. It becomes

7000/400 = 17.5 = 18

20) 628,597 1525, it becomes

600000 - 2000 = 300

Answer 2

Explanation:

1) 1) 97 – 39. It becomes

100 - 40 = 60

2)2) 812,344 – 187,675. It becomes

800000 - 200000 = 600000

3)321 + 79. It becomes

300 + 80 = 410

4) 315 x 821. It becomes

300 + 800 = 1100

5) 562 x 791. It becomes

600× 800 = 480000

6) 82 x 156. It becomes

80×200 = 16000

7) 711 x 884. It becomes

700×900 = 630000

8) 126 x 952. It becomes

100×1000 = 100000

9) 824 x 541. It becomes

800× 500 = 400000

10) 4027 x 78. It becomes

4000×80 = 320000

11) 796 x 123. It becomes

800×100 = 80000

12) 817 19. It becomes

800/20 = 40

13) 3615 72. It becomes

4000/70 = 57.1 = 60

14) 232 64. It becomes

200/60 = 33.3 = 30

15) 559 81. It becomes

600/80 = 7.5 = 8

16) 2986 222. It becomes

3000/200 = 15

17) 10275 232. It becomes

10000/200 = 50

18) 7428 286. It becomes

7000/300 = 23.3 = 20

19) 7143 369. It becomes

7000/400 = 17.5 = 18

20) 628,597 1525, it becomes

600000 - 2000 = 300