Math Is Fun Forum

snowyowl1591

Member

Registered: 2014-03-24

Posts: 3

Averages: Mean

So, I know how to figure out averages and all, but how would I figure out a question like:

"Jeremy caught 8 fishes in a competition. The mean weight of the fishes was 4.1125.

He forgot to make his own record of the weight of the last fish, but the first seven (in kgs) were: 4.4, 5.1, 6, 2.9, 3.3, 4.2 and 4.

What was the weight of the last fish?"

Is it just a trial-and-error thing, or is there a way of figuring it out? Do tell

Thanks!

Bob

Administrator

Registered: 2010-06-20

Posts: 10,643

Re: Averages: Mean

hi snowyowl1591

Welcome to the forum.

If you multiply the number in the set (8) by the mean (4.1125) you'll get back to the total.

Add up the ones you know about, subtract from the total, and what's left is the missing weight.

Bob

---

Children are not defined by school ...........The Fonz
You cannot teach a man anything;  you can only help him find it within himself..........Galileo Galilei
Sometimes I deliberately make mistakes, just to test you!  …………….Bob

snowyowl1591

Member

Registered: 2014-03-24

Posts: 3

Re: Averages: Mean

Thank you very much ^_^