The sum of four numbers is 253. The ratio of the first number to the s...
Let the 1stno. A = X
2nd no.= B , 3rd no.= C , 4th no. = D
A: B =2:3
A/B = 2/3
x/B =2/3
B= 3x/2
B:C=5:6
(3x/2)/ C= 5/6
C=( 6×3x)/2×5= 9x/5
C= 9x/5
C:D= 8:9
9x/5/ D = 8/9
D= (9x×9)/8×5= 81x/40
D= 81x/40
A+B+C+D= 253. (GIVEN)
x+ 3x/2+9x/5+81x/40
Lcm = 40
(40x+ 60x+ 72x+81x)/40= 253
253x= 253×40
X= (253×40)/253= 40
Ist no.(A)= X= 40
2no.(B)= 3x/2=( 3 × 40)/2= 60
3rd no.(C)= 9x/5 = (9×40)/5= 72
4th no.(D)= 81x/40=( 81×40/)/40= 81
Average of numbers= sum of observations/ total no.of observations
Average of 2nd no. & 3rd no.= (60+72)/2= 132/2= 66
View all questions of this test
The sum of four numbers is 253. The ratio of the first number to the s...
Given information:
- Sum of four numbers = 253
- Ratio of first number to second number = 2:3
- Ratio of second number to third number = 5:6
- Ratio of third number to fourth number = 8:9
Let's assume the four numbers as 2x, 3x, 5y, and 6y (where x and y are constants).
Using the given ratios, we can write:
- (2x + 3x + 5y + 6y) = 253 (sum of four numbers)
- 2x/3x = 2/3 (ratio of first number to second number)
- 3x/5y = 3/5 (ratio of second number to third number)
- 5y/6y = 5/6 (ratio of third number to fourth number)
Simplifying these equations, we get:
- 10x + 11y = 253
- x = (3/2)y
- x = (9/5)y
- y = 45
Therefore, the four numbers are: 30, 45, 225, and 270
The average of the second number and the third number = (45 + 225)/2 = 135
Hence, the correct answer is option D (66).