Question

câu 2.Tính bằng cách thuận tiện nhất( mẫu 3)
7/8x9/5x8/3x5

Answer 1

=7/8.8/3.9/5.5

=7/3.9

=21

Answer 2

`7/8xx9/5xx8/3xx5=[7xx3xx3xx8xx5]/[8xx5xx3]=7xx3=21`

Answer 3

\(=\dfrac{7\times3\times3\times8\times5}{8\times5\times3}=\dfrac{21}{1}=21\)

Answer 4

ai tl đi ☹

Answer 5

7/8x9/5x8/3x5

=7/8x9/5x8/3x5/1

=(7/8x8/3)x(9/5x5/1)

=      7/3   x    9/1

=          21/1

=      21