Question

Answer 1

a: \(\dfrac{2}{5}:\dfrac{3}{5}\times X+\dfrac{4}{7}=\dfrac{1}{3}+\dfrac{4}{7}\)

=>\(\dfrac{2}{3}\times X=\dfrac{1}{3}\)

=>\(X=\dfrac{1}{3}:\dfrac{2}{3}=\dfrac{1}{2}\)

b: \(B=50\times49+53\times50=50\times\left(49+53\right)=50\times102\)

 mà 102>101

nên B>A

c: Ta có: \(\dfrac{0.5}{27}< \dfrac{0.5}{15}\)

=>\(-\dfrac{0.5}{27}>-\dfrac{0.5}{15}\)

=>\(-\dfrac{0.5}{27}+\dfrac{1}{2}>-\dfrac{0.5}{15}+\dfrac{1}{2}\)

=>\(\dfrac{13}{27}>\dfrac{7}{15}\)

 

Answer 2

GIẢI NHÉ NHANH GIÚP MÌNH