a is given to us so just plug a into the first equation:
b-3 - 3b =9
Add 3 to both sides:
b-3b=12
Combine like terms:
-2b=12
Divide by -2 to get b by itself:
b=-6
The only answer with b as -6 is the first one, (-9,-6)
Answer:
5/6
Step-by-step explanation:
When dividing fractions, we use a rule where we keep the first number, change the sign, and flip the second number.
3 1/3 must be converted to an improper fraction before we can do this, though.
3 1/3 is 10/3 because we multiply 3 by the denominator, also 3, and then add one, so 10/3.
Now we can divide. Remember 4 is the same thing as 4/1
10/3 ÷ 4/1
Keep the first fraction the same, change the division sign into a multiplication sign, and divide by flip the second fraction.
It ends up looking like 10/3 x 1/4
Multiply: 10 x 1 and 3 x 4
It's 10/12, but we can simplify that by dividing both the top and the bottom by 2.
The final answer is 5/6
Answer:
4.5+2.4=6.9
Step-by-step explanation:
Fraction form: 69/10
Answer:
Keenan's z-score was of 0.61.
Rachel's z-score was of 0.81.
Step-by-step explanation:
Z-score:
Problems of normal distributions can be solved using the z-score formula.
In a set with mean
and standard deviation
, the z-score of a measure X is given by:

The Z-score measures how many standard deviations the measure is from the mean. After finding the Z-score, we look at the z-score table and find the p-value associated with this z-score. This p-value is the probability that the value of the measure is smaller than X, that is, the percentile of X. Subtracting 1 by the p-value, we get the probability that the value of the measure is greater than X.
Keenan scored 80 points on an exam that had a mean score of 77 points and a standard deviation of 4.9 points.
This means that 
So



Keenan's z-score was of 0.61.
Rachel scored 78 points on an exam that had a mean score of 75 points and a standard deviation of 3.7 points.
This means that
. So



Rachel's z-score was of 0.81.
Hey make 200 per hour, and would need 63 hours to make 12600 shirts. 63/9=7
They’d need to work for 7 days
Hope this helps