Aptitude - Ratio and Proportion - Discussion

As a total proportion of B is 2/5 of the total so the proportion of b is = 2.
and total proportion is 5; so A's proportion 5-2 = 3.
And B= 2/5 * total = 2/5*1210 = 484.
And A = 1210- 484 = 726.

Thanks.

4 * 5a = 2815b
20a = 30b
A:B = 3:2
5-1210
3-726
2-484
B = 484.

Is it necessary to find ratio of A and B? Can we find share of B directly?.

How you will find B's share directly, tell me?

4/15*(1210-B)=2/5*B
=>5B=2*1210
=>B=2*1210/5
=>B=484

Thanks bhuvi. Now I understand.

Thnx sridhar you done it nice manner.

Nothing ya. just simple.

4/15=2/5

How it will bcom equal ? just c the denominator.
4/15
If you multiply 5 by 3 u will get 15 do it in the numerator also so it becoms 6/15 for B. calculate ratio for B now 1210*6/15= 484

solution.
4/15 = 2/5
4/15 = 2/5*3/3
4/15 = 6/15
therefor A:B 4:6
1210 * 6 / 15
484

I have one more solution:

Here a+b=1210

All given possible values of b in options are :

1. 460 2. 484
3. 550 4. 664

By b's we can find a's values

1. (1210-460)=750 2. (1210-484)=726
3. (1210-550)=660 4. (1210-664)=546

Condition given: 4/15a = 2/5b then
For b's values we will check condition

1. (4/15)*750 = (2/5)*460
200 = 184 (false)

2. (4/15)*726 = (2/5)*484
193.6 = 193.6 (true)

3. (4/15)*660 = (2/5)*550
176 = 220 (false)

4. (4/15)*546 = (2/5)*664
145.6 = 265.6 (false)

So b=484 is correct.

(a+b) = 1210 given.

a4/15 = b2/5 given.

Then, a/b = (2/15)*(15/4).

=> a:b = 3:2.

Now, 3x+2x = 1210.

Then, x = 242.

So, b will be 2*242 = 484(ans).

&, a will be 3*242 = 726.