Tính nhanh các phép tính :

a) 37581-9999=27582

b)7345-1998=5347

c)485321-99999=385322

d)7393-1997=5396

a) \(37581-9999\)

\(=37581-9999-1+1\)

\(=37581-10000+1\)

\(=27581+1\)

\(=27582\)

b) \(7345-1998\)

\(=7345-1998-2+2\)

\(=7345-2000+2\)

\(=5345+2\)

\(=5347\)

c) \(485321-99999\)

\(=485321-99999-1+1\)

\(=485321-100000+1\)

\(=385321+1\)

\(=385322\)

d) \(7593-1997\)

\(=7593-1997-3+3\)

\(=7593-2000+3\)

\(=5593+3\)

\(=5596\)

Lời giải:

a. $997+86=(997+3)+(86-3)$

$=1000+83=1083$
b. $37581-9999=(37581+1)-(9999+1)$

$=37582-10000=27582$

c.

$7345-1998=(7345+2)-(1998+2)=7347-2000=5347$

d.

$485321-99999=(485321+1)-(99999+1)$
$=485322-100000=385322$

e.

$7593-1997=(7593+3)-(1997+3)=7596-2000=5596$

a: \(997+86=1083\)

b: \(37581-9999=27582\)

c: \(7345-1998=5347\)

d: \(485321-99999=385322\)

e: \(7593-1997=5596\)

37581-9999

=(37581-1)-(9999+1)

=37580-10000

=27580

7345-1998

=(7345-2)-(1998+2)

=7343-2000

=5343

hai cau con lai ban lam tuong tu nha

37581 - 9999 =  25782

7345 - 1998 =5347

485321 - 99999=385322

7593 - 1997 =5596

cách giải: tính từ phải sang trái

ai k mik mik k lại

= 5343

k cho mk nha các bn

a) 37581 - 9999 = 27582

b) 7345 - 1998 = 5347

c) 485321 - 99999 = 385322

d) 7593 - 1997 = 5596

37581-(10000-1)=27582

7345-(2000-2)=5347
485321-(100000-1)=385322

7593-(2000-3)=5596

37581-9999

7345-1998

485321-999999

7593-1997

Kết quả là bao nhiêu ạ

a. 37581 - 9999

= (37581 + 1) - (9999 + 1)

= 37582 - 10000

= 27582

b. 7345 - 1998

= (7345 + 2) - (1998 + 2)

= 7347 - 2000

= 5347

c. 485321 - 99999

= (485321 + 1) - (99999 + 1)

= 485322 - 100000

= 385322

d. 7593 - 1997

= (7593 + 3) - (1997 + 3)

= 7596 - 2000

= 5596

67 x 99 = 6 633

998 x 34 = 33 932

37581 - 9999 = 27 582

7345 - 1998 = 5347

485321 - 1997 = 483324

k mình nha

485321-9999

= 485321-(10000-1)

= 485321-10000+1

= 475321+1

= 475322

7593-1997

= 7596-2000

= 5596

- A = 485321 - 99999 = 385322

- B = 7593 - 1997 = 5596