The sum of the series below is 10900 how many numbers n are in the series 19+20.5+22+23.5++181

Consecutive terms differ by 1.5, so this is an arithmetic sequence given by

So we have

and so on, up to

The sum of the first terms is 10,900:

(we ignore the negative solution)

so there are 109 terms in the series.

Step-by-step explanation:

step-by-step explanation: if she dances 25 minutes longer then runs she would have dance 25 more minutes of running and 30 minutes of dancing to add up to 55