Problem Solving

Source: Veritas Prep

If Leo gains 10 pounds, he will weigh 50% more than his brother. Currently, their combined weight is 340 pounds. What is Leo's current weight?

A) 140
B) 160
C) 170
D) 190
E) 200

I usually post more on the verbal side because these quantitative questions get answered so quickly!

Here is the official Veritas Prep answer to this one:

Correct answer: (E)

Solution: We can set up two equations: L+10=1.5B and L + B = 340. The second equation can be written as B=340 - L, which we can plug into the first equation. L+10=1.5(340-L). L+10=510 - 1.5L. 2.5L=500. L=200.

DanaJ wrote:Source: Veritas Prep

If Leo gains 10 pounds, he will weigh 50% more than his brother. Currently, their combined weight is 340 pounds. What is Leo's current weight?

A) 140
B) 160
C) 170
D) 190
E) 200

We can plug in the answer choices, which represent Leo's current weight. Since the combined weight is 340, and at his current weight, Leo weighs almost 50% more than his brother, Leo must weigh more than 340/2 = 170. Eliminate A, B and C.

Answer choice D: Leo weighs 190
His brother weighs 340-190 = 150.
If Leo gains 10 pounds, he'll weigh 190+10 = 200.
200 is not 50% more than 150.
Eliminate D.

The correct answer is E.

340 + 10 = 350 (350 = total weight after Leo gains 10 pounds)
350 : 2.5 = 140 (140 = Leo's brother weight)
340 - 140 = 200 (200 = Leo's current weight)

L+B=340
L+10=1,5B

(substitute for L=1,5B-10)

1,5B-10+B=340
2,5B=350
B=140 ----> L=200

IMO- E is the correct answer

Here Its still better to minimise the usage of variables by selecting the Deepest encoded variable which is the Brother and we shall assign him a weight of B. If his weight is B, then Leo's weight would be 340-B.


I tried to draw a table.But was not able to do it.Its just for a better understanding.

But here are the parameters...
Row 1: IF gained 10 pounds
Row 2: Current weight

Column 1: Leo
Column 2:Brother
Column 3: Total

If Gained 10 pounds Current Weight
Leo 350-B 340-B
Brother B
Total 340



Its said that, 350-B = 50% more than B
350-B = 1.5 B
3500= 2.5B
B=140

To find the current weight of Leo, From the table above, we find that it is 340-B= 340-140= 200..

Courtesy : Ron in his Thursdays with Ron Videos

L+10=1.5B
L+B=340
Two equations and two variables
L=200, IMO - E

Answer is E.

The answer is E

l+10 = 1.5 (340-l)

l+10 = 510 - 1.5 l

2.5 l = 500

l = 200

i try and write the equations out as i read them so hear (Leo+10)=1.5*Brother and that combined Leo+Brother=340. B=340-L, plug into first equation of L+10=1.5(340-L)....2.5L=500, L=200

E wins.

Let leo's weight be "l" and his brother's weight be "b".

l+10=1.5b
l+b=340

2 equations and 2 unknowns. Solve and you get l=200.

I think the answer is E.

Quite easy, 2 equation in 2 variables

200 pounds(E)