Together 3 friends watched 411 short videos. Kelsey watched 43 more than Ekon. Ekon watched 17 less than Uma. How many videos did Kelsey watch?
Let's be accurate as possible and think first.
160
Let U = the number of videos Uma watched.

Ekon = U - 17.

Kelsey = (U - 17) + 43 = U + 26.

U + U - 17 + U + 26 = 411.

3U + 9 = 411.

3U = 402.

U = 134.

Kelsey = 134 + 26 = 160 videos.

Kelsey watched 160 videos.

.

So, the answer is 160