<span>It will take 20 minutes. The fridge needs to cool down by 90-50=40degrees. The fridge cools at 2 degrees per minute, i.e. 40/2=20 minutes total.</span>
Answer:
$968
Step-by-step explanation:
x= the money John originally had in his savings account
The statement says that John spent $88 on a radio and 1/4 of what was left on presents for his friends. This means that the remaining money is 3/4 of the total amount minus the money spent on the radio:
3/4(x-88)
Then, it says that of the money remaining, John put 4/11 into a checking account and the last remaining $420 was left to charity. Since, he spent 4/11 of the remining 3/4(x-88), the remaining is 7/11 of that and that remaining is equal to $420 that was the money left at the end:
7/11(3/4(x-88))= 420
21/44(x-88)=420
21/44x-42=420
21/44x=462
x=968
According to this, the money that John originally had in his savings account was $968.
He spent $88 on a radio: 968-88= 880
1/4 of what was left on presents for his friends: 880/4= 220
880-220=660
Of the money remaining, John put 4/11 into a checking account: 660*(4/11)=240
the last remaining $420 was left to charity: 660-240= 420
678.58 that is the surface area to this problem
Answer:
The answer is A
If x = 0 then y = 1
Step-by-step explanation:
For this case we have the following expression:
(x + 7) / (x ^ 2 - x - 2) = A / (x - 2) + B / (x + 1)
Rewriting we have:
(x + 7) / ((x-2) (x + 1)) = A / (x - 2) + B / (x + 1)
We multiply the equality by (x-2) (x + 1):
x + 7 = A (x + 1) + B (x - 2)
Rewriting we have the following system of equations:
A + B = 1
A - 2B = 7
Solving the system we have:
A = 3
B = -2
Answer:
constants A and B are:
A = 3
B = -2