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Answer:</h3>
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Step-by-step explanation:</h3>
If Alex cut his wire 18 times, he ended up with 19 equal pieces. He kept 7, so has 7/19 of his 1/3 of the wire.
Bob cut his wire 20 times, so ended up with 21 pieces, of which he kept 9. So he has 9/21 = 3/7 of his 1/3 of the wire.
Claudia kept 1/13 of her 1/3 of the wire, so has the smallest piece.
Bob kept (3/7)·(1/3)·126 cm = 18 cm.
Alex kept (7/19)·(1/3)·126 cm ≈ 15.47 cm.
Bob kept the longest part of the original wire.
Answer: 15/91 which is choice B
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There are two methods to find this answer.
Method 1) We have 6 girls and 8+6 = 14 students. The probability of picking a girl is 6/14 = 3/7. After the first girl is chosen, we have 5 girls left out of 14-1 = 13 students overall. The probability of picking another girl (assuming the first selection was a girl) is 5/13. Multiply these probabilities: (3/7)*(5/13) = (3*5)/(7*13) = 15/91
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Method 2) We can use the nCr combination formula. Order does not matter.
We have nCr = 6 C 2 = 15 ways to pick 2 girls. See the attached image below for the steps (figure 1)
Out of nCr = 14 C 2 = 91 ways to pick 2 students. See the attached image below for the steps (figure 2)
So that's another way to get the answer 15/91.
Answer:
Quinn did not make a mistake. This is because everything she did is correct and also if we calculate the expression without doing anything she did, we see that she has the right answer.
The factors of 100 are 1, 2, 4, 5, 10, 20, 25, 50, and 100 .
The factors of 65 are 1, 5, 13, and 65 .
The factors of 70 are 1, 2, 5, 7, 10, 14, 35, and 70 .
Answer: 21
Step-by-step explanation: All he did was took the amount of red and gave it a ratio of 7:1 meaning that he will increase the amount of red and make it 21 because the number 8 increased by 3 so 7 must increase by 3 as well.