The score that falls exactly in the center of a distribution of scores, such that half the scores fall below that score and half the scores fall above it, is the…

Mean

Step-by-step explanation:

You would add up all the numbers you have, then divide by however many numbers there are to get the average, or mean of the data.

answer: 1 and 3

step-by-step explanation:

, 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