From stations a to b, the distance between which is 910 mi, two trains left simultaneously moving towards each other. the speed of one train was 10 mph greater than the speed of the other one. in 5 hours the trains met. find the speed of each train.

, 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

what i would say the best answer is a. 40.5

the answer would be  

a.

3: 1

step-by-step explanation: