Question Detail

The average of four consecutive odd numbers is 24. Find the largest number.

Answer: Option B

Explanation:

Let the numbers are x, x+2, x+4, x+6, then
\begin{aligned}
=> \frac{x+(x+2)+(x+4)+(x+6)}{4} = 24
\end{aligned}

\begin{aligned}
=> \frac{4x+12)}{4} = 24
\end{aligned}

\begin{aligned}
=> x+3 = 24 => x = 21
\end{aligned}

So largest number is 21 + 6 = 27

1. The average weight of a class of 24 students is 35 kg. If the weight of the teacher be included, the average rises by 400 g. The weight of the teacher is

Answer: Option A

2. The average age of the mother and her six children is 12 years which is reduced by 5 years if the age of the mother is excluded. How old is the mother

Answer: Option C

3. When a student weighing 45 kgs left a class, the average weight of the remaining 59 students increased by 200g. What is the average weight of the remaining 59 students

Answer: Option C

Explanation:

Let the average weight of the 59 students be A.
So the total weight of the 59 of them will be 59*A.

The questions states that when the weight of this student who left is added, the total weight of the class = 59A + 45
When this student is also included, the average weight decreases by 0.2 kgs

\begin{aligned}
\frac{59A + 45}{60} = A - 0.2
\end{aligned}

=> 59A + 45 = 60A - 12
=> 45 + 12 = 60A - 59A
=> A = 57

4. Average of five numbers is 27. If one number is excluded the average becomes 25. The excluded number is

Answer: Option A

Explanation:

Number is (5*27) - (4*25) = 135-100 = 35

5. Average of 10 numbers is zero. At most how many numbers may be greater than zero

Answer: Option D

Tanvee 11 years ago

If its odd number then we need to to take x,x+1,x+3,x+5.... why we are taking even number?

mastguru 11 years ago replied

Hello Tanvee,
We are taking X as an odd number,
so, other consecutive odd number will be x+2 and another will x+4 and so on..
Lets say 1 is odd number, then next will 1+2 =3, 1+4 =5.. and so on.
In this way we are solving this problem.
Admin 11 years ago

Thanks Nagendar. It was a typing mistake. Question was about four consecutive odd numbers.
We appreciate your feedback.
nagendar 11 years ago

here x is an even number. but you got x=21(which is not even number). so consecutive even numbers are: 2x,2x+2,2x+4,2x+6.