so my math teacher made us do a review and I forgot how to do 8.90 x 15 bc when I do it's not in the multiple choices help

133.5

Step-by-step explanation:

133.5

An easy way of doing this is to ignore the decimal so consider it as 89 instead because 0 is insignificant. So do 89x15 = 1335 we know that 8.90 has 1 decimal place because 0 is not significant so you just add 1 decimal place which becomes 133.5

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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

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