8000(.09)=720 8000+720=8720
11x11=121
$140-121=19
19/7=
It would take approximately 2hours and 71 minutes to meet her requirements.
Full question attached
Answer:
Paired t test
Explanation:
The paired sample t test is used to measure or compare the mean of two observations or samples by measuring each subject two times as is seen above with the gold measurement which would result in two sets or pair of samples in a statistical procedure. We observe from the question that we measure each gold with two methods and then compare result of the two methods in terms of their mean error using the paired t test.
Answer: Either 2, 5, or 8
This means the number 426 is divisible by 6. So are 456 and 486
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Explanation:
A number is divisible by 6 if both of the following are true
- The number is divisible by 2
- The number is divisible by 3
This is simply because 6 = 2*3. So if 6 is a factor of a number, then 2 and 3 must be factors.
- To have 2 be a factor, the units digit must be in the set {0,2,4,6,8} which is the case here (the units digit is 6 in this case). Therefore we know the number is a multiple of 2 regardless of what the other digits are.
- To have 3 be a factor, the digits must add up to a multiple of 3. Through trial and error, we see that 0 doesn't work because 4+0+6 = 10 which is <u>not</u> a multiple of 3. Same goes for 4+1+6 = 11, but 4+2+6 = 12 is a multiple of 3.
Therefore, 426 is a multiple of 6
Increment that middle digit 2 by 3 and we jump from 426 to 456. Those three digits add to a multiple of 3 as well (4+5+6 = 15). Following that line of logic, we go from 456 to 486 as the last possible three digit number that has these conditions of having 4 first and 6 last, and the number is a multiple of 6.
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In short,
The numbers 426 and 456 and 486 are all multiples of 6 since they are multiples of 2 and 3 at the same time.
So we could replace that middle digit with either 2, 5 or 8.
