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Numerical Ability
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2/3rd of the balls in a bag are blue, the rest are pink. if 5/9th of the blue balls and 7/8th of the
pink balls are defective, find the total number of balls in the bag given that the number of non
defective balls is 146.
a) 216 b) 649 c) 432 d) 578
Read Solution (Total 11)
-
- let total no of balls =x
blue=2x/3
pink=x/3
total no of defective balls = 10x/27 +7x/24
=143x/216
non defective balls=x-143x/216=146
x=432
- 10 years agoHelpfull: Yes(61) No(7)
- total no of defective balls = 10x/27 +7x/24
=143x/216
can u explain this step how it will cum!! - 10 years agoHelpfull: Yes(11) No(2)
- let the total balls be x
2/3x=blue & 1/3x=pink
non defective balls=146
total no. of balls=defective+non defective
hence defective=total-non defective(146)
(2/3x)*5/9+(1/3x)*7/8=t-146
0.66203x=t-146
146=0.3303x
x=432 - 10 years agoHelpfull: Yes(10) No(4)
- Let the total numbers of the ball in a bag is x.
Blue balls = 2/3 of x and Pink ball = x - 2x/3 = x/3
Defective Blue balls = 5/9 of (2/3 of x) = 5/9 × 2/3 × x = 10/27 × x
Defective Pink balls = 7/8 of x/3 = 7x/24
Now, According to the Question, Non Defective Blue and Pink balls = 146
Total no. of balls=defective+Non defective
Non defective=Total -Defective
x - ( 10x/27 + 7x/24) = 146
x - ( 8(10x) + 9(7x) / 216 ) = 146
x - (80x + 63x)/216 = 146
x - 143x/216 = 146
x = 432 - 6 years agoHelpfull: Yes(5) No(0)
- Non defective blue ball + Non defective pink ball =146
(5/9)(2x/3)+(7/8)(1x/3)=146
10x/27+7x/24=146
x=432 - 10 years agoHelpfull: Yes(4) No(0)
- 216 and 578 both exactly divisible by 3, but 216 is very small so take the 578.
ANS D:578*2/3=288 blue balls & 578-288-144 pink balls.
288*5/9 defective=160 defective blue balls & 144*7/8=126 defective pink balls.
and the 288-160= 128 non defective blue balls and 144-126=18 non defective pink balls. add both 128+18 = 146 non defective balls. VIKASH KUMAR SINGH(JNU ECE) - 10 years agoHelpfull: Yes(3) No(3)
- pls explain how 10x/27 +7x/24 come from
- 10 years agoHelpfull: Yes(1) No(0)
- 2/3x*5/9=10/27x
and x/3*7/8=7x/24 - 10 years agoHelpfull: Yes(1) No(0)
- @anbarasan lcm of 10x/27+7x/24
- 10 years agoHelpfull: Yes(0) No(0)
- lcm of 27,24 = 216 (Check in net if you dont know lcm)
- 6 years agoHelpfull: Yes(0) No(1)
- Ans = 432
let total balls = x
blue balls =2/3x
pink balls= 1/3x
defective balls =5/9(blue) + 7/8(pink) => 5/9 (2/3x) +7/9(1/3x)
Non defective = x - defective balls
146= x- 5/9 (2/3x) +7/9(1/3x)
146 = (216x -143x)/216
146=73x / 216
x= (146*216) /73 =432 - 6 years agoHelpfull: Yes(0) No(0)
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