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**cooljackiec**- Replies: 2

{a} denotes the fractional part of a

I got (a+2e-3)^2=(a+3e+2)(a+e-4) which gives 10a+e^2+22e-4=0

Derp I thought that 3^0+1 was 1 my bad

I tried S=the thing posted and S/3, not exactly sure how to do it, I have 3^k/(3^k+1)

bob bundy wrote:

with r = common ratio.

So eliminate b, c and d from the GP equations and then divide the first by the second and first by the third to eliminate r and leave a pair containing just a and e.

How exactly do you "eliminate b"

Using the above, how would you get 2?

Sounds intuitive, can you try to explain what your thought process was?

o.O how in the world do you get that...

I used the method before I posted but didn't get anywhere

**cooljackiec**- Replies: 14

Find the arithmetic sequence a, b, c, d if a−2, b−4, c−3, d+2 is a geometric sequence.

**cooljackiec**- Replies: 12

I have no clue either.

**cooljackiec**- Replies: 10

Compute

**cooljackiec**- Replies: 2

A country has three denominations of coins, worth 7, 10, and 53 units of value. What is the maximum number of units of currency which one cannot have if they are only carrying these three kinds of coins?

I know the formula for 2 denominations, but I don't know how to do one with 3.

is the number of divisors of n

Thanks, this doesn't exactly relate to bases, but:

Find all positive integers n such that

.Given a rational number, write it as a fraction in lowest terms and calculate the product of the resulting numerator and denominator. For how many rational numbers between 0 and 1 will 20! be the resulting product?

We have fraction m/n. I wrote the prime factorization of 20!, but I can't seem to find the largest possible value of m. Once I get the largest value of m, then I can just count the number of divisiors of m, but what do I do to get m.

Also:

Find the sum of all positive rational numbers that are less than 10 and that have denominator 30 when written in lowest terms.

Hmm 32/127 is what i found too

Also, anonimistefy, I got the 1st question. It was 30, not 32.

so apparently, we can have 2513 and stuff. So like we just need 251 in order and then can have extra digits. 251 /999 is interesting, because 251 is close to 250, a divisor of 1000, which is cllose to 999.

Anyways, idk about the 1st quesiton

EDIT: we don't need to have a repeated decimal