Aptitude - Problems on Numbers - Discussion

Discussion Forum : Problems on Numbers - General Questions (Q.No. 2)
2.
Three times the first of three consecutive odd integers is 3 more than twice the third. The third integer is:
9
11
13
15
Answer: Option
Explanation:

Let the three integers be x, x + 2 and x + 4.

Then, 3x = 2(x + 4) + 3      x = 11.

Third integer = x + 4 = 15.

Video Explanation: https://youtu.be/_77C9YE321Y

Discussion:
75 comments Page 4 of 8.

Gayathri Ganesan said:   10 years ago
I got idea about this solution. But if we assume the solution by question as,

3 times the x of three consecutive integers whether is my assumption also possible na.

3(x+X+2+x+4) = 3+2(x+4) // I consider it for first 3 con int respectively.

Anyone can explain my logic please.

Sony said:   10 years ago
At first three number is x, x+2, x+4 these are three consecutive number.

Then according to question (three times the first of three consecutive odd number) here is our first number is x then,

Our first condition will be 3x----- (1).

And then 3 more than twice the third (there third is x+4).

3 more means 3+, twice means 2.

Then twice of third is 2(x+4).

Then again 3+2(2x+4) -------- (2).

Then from equation first and second we get:

3x = 3+2(x+4).
3x = 3+(2x+8).

3x = 3+2x+8.
3x-2x = 11.
x = 11.

Then our third integer is x+4 ==> 11+4 = 15.

Our third integer is (x+4) = 15.

HYNDAVI said:   1 decade ago
But whats the reason to multiply 3 on both sides?

Aandrew said:   1 decade ago
Can any one say how to solve this in 32 seconds?

Reshma said:   1 decade ago
If you take x+1 as first odd no. Then put 1 in the place of x, it becomes 1+1=2 its not odd integer you got it.

Gayathri said:   1 decade ago
Three consecutive odd numbers x+1, x+3, x+5.

(x+1)+(x+3)+(x+5) = 3+2(x+5).

x = 4. So the third integer x+5 = 4+5 = 9.

I think the answer will be 9 because in this problem three consecutive odd numbers is asked then, how can we start with 0 is my doubt.

HEMANTH REDDY G said:   1 decade ago
3 times of 1st consecutive means 3x.
Twice of 3rd consecutive 2(x+4).

3 more than twice of 3rd consecutive 2(x+4)+3, then.

3x = 2(x+4)+3.
3x-2x = 8+3.
x = 11.

3rd integer is x+4 = 11+4 = 15.

Neeraj upadhyay said:   1 decade ago
Three consecutive integer are 2x+1, 2x+3, 2x+5.

Now according to question.

3(2x+1) = 2(2x+5)+3.

6x+3 = 4x+10+3.

2x = 10.

x = 5.

And now third number is 2x+5 = 2*5+5 = 15.

15 is a answer.

Ssgm said:   1 decade ago
An integer n any odd will be (2n+1).
After (2n+1) is (2n+3) then (2n+5).

From the Q:
3(2n+1) > 2(2n+5).

=> n > 3.5 => n start from 4 to infinity.

So the numbers (2(4)+1=9), 11, 13 and I say the answer is 13.

V.Ranjitha said:   1 decade ago
Hi friends,

I think Govind is correct. Because the x value may be odd number or even number.(2x+1,2x+3,2x+5)

If x=0,
We get 1, 3, 5.

If x=1(odd),
We get 3, 5, 7.

If x=2(even),
We get 5, 7, 9.


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