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A family keeps a bowl that contains ping-pong balls labeled with chor
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18 Jul 2022, 00:37
18 Jul 2022, 00:37
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Question Stats:
100% (01:22) correct
0% (00:00) wrong based on 3 sessions
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A family keeps a bowl that contains ping-pong balls labeled with chores: tidy the hallway, wash dishes, mop kitchen floor, clean upstairs bathroom, vacuum living room, fold laundry, clean downstairs bathroom, and make the beds. One child particularly hates to use the vacuum cleaner. At chore time, she draws out two balls and must complete the chores written on them. What is the chance that she will avoid having to vacuum?
A 49/64
B 1/4
C 3/4
D 7/4
E 97/56
A 49/64
B 1/4
C 3/4
D 7/4
E 97/56
Part of the project: GRE QCQ & PS 3 Questions Every One DAILY Challenge - (2022)
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GRE Math Essentials (2022)
GRE Geometry Formulas for a Q170
GRE - Math Book
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GRE Math Essentials (2022)
GRE Geometry Formulas for a Q170
GRE - Math Book
Re: A family keeps a bowl that contains ping-pong balls labeled with chor
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19 Jul 2022, 01:48
19 Jul 2022, 01:48
Expert Reply
OE
Quote:
Explanation: On her first draw, she has 7 out of 8 possible chances to avoid the vacuuming. If she is successful and the vacuum ball remains in the bowl, 6 of the remaining 7 balls are non-vacuum. So her chances overall of avoiding the vacuum job are 7/8*6/7=6/8=3/4 Remember to cancel the 7’s in the numerator and denominator and to factor out the 2 in the 6 and 8, to save multiplication trouble and leave the result in lowest terms.
Re: A family keeps a bowl that contains ping-pong balls labeled with chor
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19 Jul 2022, 02:08
19 Jul 2022, 02:08
1
The question here asked is similar to: What is the probability of not choosing 1 from a set of 1-8.
So it is basically probability of choosing 2 from 7 remaining.
Hence the answer,
7C2/8C2
where, 8C2 is the total number of possible ways.
So it is basically probability of choosing 2 from 7 remaining.
Hence the answer,
7C2/8C2
where, 8C2 is the total number of possible ways.
