Đáp án:
Giải thích các bước giải:
$\dfrac{\dfrac{\dfrac{1}{2}+\dfrac{1}{3}+\dfrac{1}{4}+\dfrac{1}{5}}{\dfrac{2}3+\dfrac{3}{4}+\dfrac{4}{5}+\dfrac{5}{6}}}{\dfrac{\dfrac{3}2+\dfrac{4}{3}+\dfrac{5}{4}+\dfrac{6}{5}}{\dfrac{3}{4}+\dfrac{4}{7}+\dfrac{7}{10}+\dfrac{10}{13}}}$
= `( 1/2 + 1/3 + 1/4 + 1/5 ) : ( 2/3 + 3/4 + 4/5 + 5/6 ) : ( 3/2 + 4/3 + 5/4 + 6/5 ) : ( 3/4 + 4/7 + 7/10 + 10/13 )`
= `77/60 : 61/20 : 317/60 : 5079/1820`
= `77/183 : 317/60 : 5079/1820`
= `1540/19337 : 5079/1820`
= `0,0285.......`