Clearly, the brother of woman's mother is the same as the brother of the father of boy's maternal uncle. So, the woman's mother's brother is the boy's maternal uncle's father. Thus the woman's mother's brother's son is boy's maternal uncle, i.e woman's mother's  brother's daughter is boy's mother.

For a triangle, we need 3 non-collinear points. So with 12 points (when all the 12 are such that any three non-collinear is12C3. But among them 8 points are collinear.

If all these 8 points are different we get 8C3 triangles as they are collinear.

In 12C3 triangles, we do not get 8C3 triangles

Therefore, The number of triangles we get = 12C3-8C3 = 164

Let M and m grams be the mass of boat + rock in it. By law of floatation(M+m) grams of water will be displaced. This has a volume of (M+m)cc. That means the level of water in pool has risen up by (M+m)cc with the boat + rock when it is floating. If the rocks in the boat are thrown not into the pool but outside, the weight left is only M grams the weight of the boat. This will have displaced M cc of water only i.e less water than in the case of loaded boat. But if the rocks are put in the water in the pool and not outside, then the water in the pool will rise not only by M cc on account of empty boat but also by a volume of the stone put into it. This volume will be mdwhere m is the mass of rock and d density of rock.

Now md is  < m. Thus the total rise will be M+mdwhich is < M + m.

Effect of adding liquid is to make the cylinder more bottom heavy which is a more stable position

Clearly, the required number would be such that it leaves a remainder of 1 when divided by 3, 4, 5, or 6 and no remainder when divided by 7. Thus, the number must be of the form (L.C.M of 3, 4, 5, 6) x + 1 i.e., (60x + 1 ) and a multiple of 7. Clearly, for x = 5, the number is a multiple of 7. So the number is 301.

Interest received by A from B = 10% of half of Rs.50000 = 10% of Rs. 25000 = Rs.2500.

Amount received by A per annum for being a working partner = 1500 x 12 = Rs.18000

Let 'P' be the part of the remaining profit that A receives as his share.

So,total income of A = (Rs.2500 + Rs.18000 + Rs. P )

Total income of B = only his share from the remaining profit = 'P', as  A and B share the remaining profit equally.

We know that income of A = Twice the income of B 

So, (2500 + 18000 + P ) = 2(P)

P = 20500

Thus, the total profit = 2P + Rs.18000

= 2(20500) + 18000 = Rs.59000.