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:
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:
76 comments Page 8 of 8.
Pinky said:
5 years ago
My answer is 15.
Let 2n+1 be an odd number for any value of n from 0 up to infinity.
Take a look: If n=0, 2n+1 is 1. If n=1, 2n+1 is 3. See, the resulting number is always odd whether n is odd or even.
Let (2n+1), (2n+3), (2n+5) be the three consecutive numbers.
Just to see if these three are really consecutive odd, let us try to substitute n=0. If n=0, the resulting three consecutive odd are 1,2,3. If n=1, the resulting three consecutive odd are 3,5,7. This is just to show you that these three will really result to three consecutive odd for any value of n from 0 up to infinity.
Since we do not know exactly what are these three consecutive odd, so let us take these (2n+1), (2n+3), (2n+5) as the three consecutive odd numbers.
Solution:
3(2n+1) = 2(2n+5)+3
6n+3 = 4n+10+3
6n-4n = 10+3-3
2n = 10
n = 5.
Since the third odd number is represented by 2n+5, just substitute 5 to n. So the third odd number is 15.
We can also say that the three consecutive odds are 11, 13, 15. The third is 15.
Let 2n+1 be an odd number for any value of n from 0 up to infinity.
Take a look: If n=0, 2n+1 is 1. If n=1, 2n+1 is 3. See, the resulting number is always odd whether n is odd or even.
Let (2n+1), (2n+3), (2n+5) be the three consecutive numbers.
Just to see if these three are really consecutive odd, let us try to substitute n=0. If n=0, the resulting three consecutive odd are 1,2,3. If n=1, the resulting three consecutive odd are 3,5,7. This is just to show you that these three will really result to three consecutive odd for any value of n from 0 up to infinity.
Since we do not know exactly what are these three consecutive odd, so let us take these (2n+1), (2n+3), (2n+5) as the three consecutive odd numbers.
Solution:
3(2n+1) = 2(2n+5)+3
6n+3 = 4n+10+3
6n-4n = 10+3-3
2n = 10
n = 5.
Since the third odd number is represented by 2n+5, just substitute 5 to n. So the third odd number is 15.
We can also say that the three consecutive odds are 11, 13, 15. The third is 15.
(3)
Aryan said:
4 years ago
Here
Three odd consecutive number.
3, 5, 7 = 3 + 5 + 7 then ans 15.
Three odd consecutive number.
3, 5, 7 = 3 + 5 + 7 then ans 15.
(33)
Tashi Tshering said:
4 years ago
Here,
1,3,5 three odd consecutive no;
Three times the first of three consecutive odd integers is 3 more than twice the third,
3x when the third inter is x=5.
3*5=15.
1,3,5 three odd consecutive no;
Three times the first of three consecutive odd integers is 3 more than twice the third,
3x when the third inter is x=5.
3*5=15.
(12)
Megersa Tadale said:
3 years ago
Suppose we take x,x+2,x+4 for odd consecutive numbers;
Then, according to the question, the first among the consecutive number is 3 more than twice the third number.
It means 3x+3=2(x+4) then;
we will get 3x+3=2x+8(now collecting like terms);
then 3x-2x=8-3.
x=5
So the third number is x+4----->>>> 9.
Then, according to the question, the first among the consecutive number is 3 more than twice the third number.
It means 3x+3=2(x+4) then;
we will get 3x+3=2x+8(now collecting like terms);
then 3x-2x=8-3.
x=5
So the third number is x+4----->>>> 9.
(5)
Mahendrakumar said:
1 year ago
The first three odd numbers,
X, X+2, X+4.
in the question they've mentioned 3 times the 1st odd number(which is X)
So, 3X.
Then they've mentioned 3 more than twice of the third number 3+2(X+4).
then;
3x = 3+ 2(x + 4).
3x = 3+ 2x + 8.
3x - 2x = 3 + 8.
x = 11.
So, the ans is 11 +4 => 15.
X, X+2, X+4.
in the question they've mentioned 3 times the 1st odd number(which is X)
So, 3X.
Then they've mentioned 3 more than twice of the third number 3+2(X+4).
then;
3x = 3+ 2(x + 4).
3x = 3+ 2x + 8.
3x - 2x = 3 + 8.
x = 11.
So, the ans is 11 +4 => 15.
(18)
Sandhiya said:
1 week ago
In this question, they have mentioned that three odd integers should be more than twice the third integer, but in simple we can take 3 as mentioned in the question. After three, let's take two more odd numbers 3, 5, 7. When we add all this, we will get an answer of 15.
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