The toy horse collection contains 10 horses. You purchase the set and then sell 3 horses to Kate. If you only charge the exact price (no tax involved), how much does Kate pay you?

three tenths of the original amount

Let's start.

There are 10 horses.

(Buying the set is not important, since it does not affect this scenario.)

You sell three horses to Kate, and you expect her to give you the exact price.

Let's say that 10 horses cost the total (unknown).

10 horses equal the total amount, or 1

10 to 1

Now, you sell 3 of these horses. You must multiply 10 and n to make 3.

10 x n = 3

10x 3/10 = 3

Do the same to the other side.

1 x 3/10 = 3/10

3 to 3/10

, and

for

step-by-step explanation:

we can analyze the pattern at which the terms increase. let us denote , , , so that we can call

note the following:

the pattern: to get the next term value, we just add the next term number (e.g. 1st, 2nd, to the previous term value (term values are the given numbers in the question, 1, 3, 6, 10, 15,

from , to get to , we add

from , to get to , we add

etc.

we need to form a recursive formula, a formula that has the next term as a function of the previous term. so a possible recursive formula can be

, and for

hello from mrbilldoesmath!

answer:

25x^2 + 90x + 84

discussion:

mn(x) = m(n(x)) = m( 5x + 9) =

(5x + 9)^2 + 3 =>

25x^2 + 90x + 9^2 + 3 =

25x^2 + 90x + 84                 (as 9^2 = 9*9 = 81)

which is the second choice

regards,  

mrb

p.s.   i'll be on vacation from friday, dec 22 to jan 2, 2019. have a great new year!