He worked as a carpenter for 12 hrs. and as a blacksmith for 18.
Answer:
6kg pure copper and 30 kg 10% copper was mixed to give 36kg of 25% alloy
Step-by-step explanation:
Here, we want to produce 36 kg of 25% alloy
Let the Pure copper be x kg while 10% alloy be y kg
Pure copper is simply 100% copper
Thus;
x + y = 36 •••••(i)
Then;
100% of x + 10% of y = 25% of 36
= x + 0.1y = 9 •••••• ii)
From i x = 36-y
from ii, x = 9-0.1y
Equate both x
36-y = 9-0.1y
36-9 = 0.1y + y
0.9y = 27
y = 27/0.9
y = 30
x = 36-y
x = 36-30
x = 6 kg
Answer:
9 cents per day
Step-by-step explanation:
1 week = 7 days
Each razor lasts 1 week = 7 days
10 razors last 10 weeks = 10 * 7 days = 70 days
cost per day = (total cost)/(number of days)
cost per day = $6.30/(70 days) = $0.09/day
Answer: standard deviation = 8
This is because mu = 75 is the mean, which is at the very exact center of this distribution. One space to the right is 83, which is 83-75 = 8 units away from the center. This distance is exactly one standard deviation. We can say "83 is one standard deviation larger than 75".
Or you could note the distance from 67 to 75 is also 8, because 75-67 = 8. Each tickmark represents stepping one standard deviation in distance.
