either i didn't learn the maths correctly in Primary school , (150/63) / (2/21) = (150/63) * (21/2) = 55 How can it be 55 should be 25 right ?

The way to solve it is not that difficult

Step-by-step

First the numerator

\(\frac{25}{7}+\frac{35}{3}=\frac{110}{21}\)

Second the denominator

\(\frac{14-12}{21}=\frac{2}{21}\)

Combine the reverse of the second fraction and we do have

\(\frac{110}{21}*\frac{21}{2}=\frac{110}{2}=55\)

E is the answer.

The numerator is 12/7 + 2/3. That comes to 50/21. Can someone clarify?

The numerator is \(3*\frac{4}{7}= \frac{3*7+4}{7}=\frac{25}{7}\)

I hope now is clear for mixed fraction

See here for more theory https://gre.myprepclub.com/forum/gre-ma ... tml#p97122

its actually in mixed fraction form. even i got confused initially. 3 4/7 = 21+4/7 = 25/7
similarly 1 2/3 = 5/3
25/7 + 5/3 = 75+35/21 = 110/21 (numerator)
2/3-4/7 = 2/21
Therefore, 110/21/2/21 = 55

\(\frac{3\frac{4}{7}+1\frac{2}{3}}{\frac{2}{3}-\frac{4}{7}}=\)

\(\frac{\frac{(3*7 + 4)}{7}+\frac{(1*3 + 2)}{3}}{\frac{7*2 - 4*3}{3 * 7}}=\)

\(\frac{\frac{25}{7}+\frac{5}{3}}{\frac{14 - 12}{21}}=\)

\(\frac{\frac{25 * 3 + 5 * 7}{21}}{\frac{2}{3 * 7}}=\)

\(\frac{75 + 35 }{ 2}\) = \(\frac{110}{2}\) = 55

So, Answer will be E
Hope it helps!

Watch the following video to learn about Butterfly Method of Adding Fractions!

Video Link

Fixed guys. My fault. I do not know how the multiplication sign was over there.

My bad

Now it makes more sense

I am sorry could happen