3 years ago

How many 7 digit phone numbers are there assuming the first digit can't be a 0 or a 1?

1 answer:

7 0

The first digit can be any one of the numbers 2-9 That a total of 8 numbers.

The next 6 digits can be any permutation of 6 from the numbers 0 to 9.
(10 numbers)

nPr = n! / r!

so here we have 10P6 = 10! / 6! = 10*9*8*7 = 5040

So final answer is 8 * 5040 = 40,320

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[geometry] i got 267.94 but how do i answer that in fraction?

Firlakuza [10]

Well, first off, you see how all the answers say a fraction, then pi? that means that you don't calculate pi into your answer.
But lets see. The radius is 4. V=(4/3)pi*r^2
V=(4/3)pi*4^2
V=(4/3)pi*16
V=(4/3)*16*pi
V=(4/3)*(16/1)*pi
V=(4*16)/(3*1)*pi
V=64/3*pi
so the answer is (B) 64/3pi units cubed.

8 0

3 years ago

You bought a new car for $15,000 and know that it loses 1 5 of its value every year. The equation that models the value of your

Whitepunk [10]

Given that the value of the car is given by the function:
y=15000(1/5)^x
the graph will be represented as follows:

From the graph we see that the domain is all real numbers.