Question

Thực hiện phép tính bằng cách hợp lí:

a) ( 9/25 - 2.18) : ( 19/5 + 0,2 )

Answer 1

(\(\dfrac{9}{25}\) - 2.18) : (\(\dfrac{19}{5}\) + 0,2)

=(\(\dfrac{9}{25}\) - 2.18) : (\(\dfrac{19}{5}\) +\(\dfrac{1}{5}\) )

=(\(\dfrac{9}{25}\)- 36) : 4

=\(\dfrac{-117}{5}\) : 4

= \(\dfrac{-117}{20}\)

Answer 2

(\(\dfrac{9}{25}\)-2.18) : (\(\dfrac{19}{5}\) +0,2)

= (\(\dfrac{9}{25}\)- 2.18) : (\(\dfrac{19}{5}\)+\(\dfrac{1}{5}\))

= (\(\dfrac{9}{25}\)-36): 4

= \(\dfrac{-891}{25}\):4

=\(\dfrac{-891}{100}\)