First, we have to get the fractions to common denominators.
4/5 = 16/20
1/4 = 5/20
5 5/20 - 3 16/20 = 1 9/20
She put 1 9/20 extra cups in.
The probability that the bulb is good is 12/15.
Since we have taken 1 item out the remaining total is now 14, so the probability of getting a defective bulb is now 3/14.
Now you multiply the probabilities together to get (12/15)(3/14)=(4/5)(3/14)=12/70=6/35
Answer:
A
Step-by-step explanation:
In the monthly payment formula r is the percentage rate as a decimal.
To turn a percentage into a decimal, move the decimal point 2 places to the left.
5.7% becomes 0.057
Let n = number of nickels, and p = number of pennies.
The number of coins is 25, so we get this equation.
n + p = 25
The value of the coins is 0.05 per nickel, and 0.01 per penny.
0.05n + 0.01p = 0.73
Now you have a system of equations.
n + p = 25
0.05n + 0.01p = 0.73
Solve the first equation for n:
n = 25 - p
Now substitute into the second equation.
0.05(25 - p) + 0.01p = 0.73
1.25 - 0.05p + 0.01p = 0.73
-0.04p = -0.52
p = 13
There were 13 pennies.
Now we substitute 13 for p in n + p = 25 to find out the number of nickels.
n + 13 = 25
n = 12
There are 13 pennies and 12 nickels.
Check: 13 pennies and 12 nickels does total 25 coins.
13 * 0.01 + 12 * 0.05 = 0.13 + 0.60 = 0.73
The value is $0.73.
Our answer is correct.
