47.63 = (55 - 8)(55 + 8)

= 55² - 8²

= 3025 - 64

= 2961

--------

47.(63 - 15) - 63.(47 - 15)

= 47.63 - 47.15 - 63.47 + 63.15

= 47.(63 - 63) + 15.(63 - 47)

= 47.0 + 15.16

= 0 + 240

= 240

47.63 = (55 - 8)(55 + 8)

= 55² - 8²

= 3025 - 64

= 2961

--------

47.(63 - 15) - 63.(47 - 15)

= 47.63 - 47.15 - 63.47 + 63.15

= 47.(63 - 63) + 15.(63 - 47)

= 47.0 + 15.16

= 0 + 240

= 240

99 x 15 + 15 = 15 x ( 99 + 1) = 15 x 100 = 1500

= 15x 4 + 15 x 96

= 15x (4+96)

= 15x 100

=1500

15: 0,25+ 15 x 96 

15 x 4 + 15 x 96

15 x (4 + 96)

15 x 100

1500

1111+2517536251673521735123517338276349-24546575643356435321=

15 x 6= 90

+ 48= 138 nha 

=7x15 + 3x15 + 15x2 -30

=15x(7+3+2)-30

=15x12-30

=180-30

=50

2370

k cho tớ nhé

nhầm 150 nhé

=452.(17+98-15)

=452.100

=45200

=452 x(17+98-15)

=452 x 100

=45200

\(452\times17+452\times98-452\times15\)
\(\Rightarrow452\times\left(17+98-15\right)\)
\(\Rightarrow452\times100\)
\(\Rightarrow45200\)

1/4

\(=\dfrac{8}{15}\left(\dfrac{25}{32}-\dfrac{10}{32}\right)=\dfrac{8}{15}\cdot\dfrac{15}{32}=\dfrac{1}{4}\)

( 25/32 - 10/32) x 8/15

 = 15/32 x 8/15

= 1/4

= \(\dfrac{4}{15}\) x ( 3 + 2 - 5 )

=  \(\dfrac{4}{15}\) x 0

= 0

( 3+2-5) x 4/15

=  0        x 4/15

=  0

( 3+2-5) x \(\dfrac{4}{15}\)

=  0  x \(\dfrac{4}{15}\)

=0

\(15.8-15-8+15.8+15-8\)

\(=15.\left(8-1+1\right)+8.\left(15-1-1\right)\)

\(=15.8+8.13\)

\(=8.\left(15+13\right)\)

\(=8.28\)

\(=224\)

15.8 − 15 − 8 + 15.8 + 15 − 8
= 15. (8 − 1 + 1 )+ 8. (15 − 1 − 1)
= 15.8 + 8.13
= 8. (15 + 13)
= 8.28
= 224
 

  15 . 8 - 15 - 8 + 15 . 8 + 15 - 8

= 15 . 8 - 23 + 15 . 8 + 7

= 15 . 8 + 15 . 8 - 23 + 7

= 15 . ( 8 +8 ) - ( 23 - 7 )

= 15 .16 - 15

= 15 . ( 16 - 1 )

= 15 . 15

= 225