Question

A, \(\dfrac{1}{8}\) +\(\dfrac{1}{32}\)+\(\dfrac{1}{72}\)=??

B,\(\dfrac{24}{35}\).\(\dfrac{7}{8}\)=??

C,\(\dfrac{34}{35}\)-\(\dfrac{3}{7}\)-\(\dfrac{2}{5}\)=??

D,\(\dfrac{16}{32}\)-\(\dfrac{48}{56}\)=??

a, \(\dfrac{15}{17}\).\(\dfrac{4}{5}\)+\(\dfrac{1}{5}\).\(\dfrac{15}{17}\)=??

b,\(\dfrac{29}{12}\):\(\dfrac{1}{2}\)-\(\dfrac{5}{12}\):\(\dfrac{1}{2}\)=??

3,một hình chữ nhật chiều dài \(\dfrac{1}{4}\) ,chiều rộng \(\dfrac{3}{10}\).tính chu vi và diện tích hình chữ nhật.

các bạn giúp mình với nhé

Answer 1

3/ Chu vi hình chữ nhật:

\(\left(\dfrac{1}{4}+\dfrac{3}{10}\right)\cdot2=\dfrac{11}{10}\) (chưa biết đơn vị)

Diện tích hình chữ nhật:

\(\dfrac{1}{4}\cdot\dfrac{3}{10}=\dfrac{11}{20}\) (chưa biết đơn vị)

Answer 2

A, \(\dfrac{36}{288}+\dfrac{9}{288}+\dfrac{4}{288}=\dfrac{49}{288}\)

b,\(\dfrac{3}{5}\)

c,\(\dfrac{34}{35}-\dfrac{15}{35}-\dfrac{14}{35}=\dfrac{1}{7}\)

d,\(\dfrac{1}{2}-\dfrac{6}{7}=\dfrac{7}{14}-\dfrac{12}{14}=\dfrac{-5}{14}\)

a.\(\dfrac{15}{17}.\left(\dfrac{4}{5}+\dfrac{1}{5}\right)=\dfrac{15}{17}.1=\dfrac{15}{17}\)

b,\(\dfrac{1}{2}:\left(\dfrac{29}{12}-\dfrac{5}{12}\right)=\dfrac{1}{2}:\dfrac{24}{12}=\dfrac{1}{4}\)