Two varieties of tomatoes are bought in the ratio 2 : 3, where the price of first variety is twice that of the
second. The varieties are mixed and sold at Rs.17.50 per kg, resulting in a profit of 25%. Find the costs of the two varieties before selling.

Let say, first quality and second quality of tomato bought are 2k and 3k.

And price of first quality and second quality are 2x per kg and x per kg.

Total cost price of first quality=4kx and second quality=3kx.

per kg price=$$\frac{\left(4kx+3kx\right)}{\left(2k+3k\right)}=\frac{7kx}{5k}=1.4x.$$

So,

$$1.4x\times1.25=17.50.$$

or,$$x=\frac{17.50}{1.4\times1.25}=10.$$

So, before selling their cost price was 20 and 10 Rs.

B is correct choice.