Posted by **Katherine** on Wednesday, November 10, 2010 at 5:02pm.

kyle had 36 books in hislocker. some were library books, some were textbooks, and the rest were telophone books. the number of library books and textbooks combined equal twice the number of textbooks. the number of textbooks and telephone books combined equals three times the number of library books. how many of each type of book were in kyle's locker??

please help me....i need a chart or a rule to show me how u got it....please

- math -
**Mrs W**, Wednesday, November 10, 2010 at 6:12pm
Do it this way

a=library books

b=textbooks

c=telephone books

You know a + b + c = 36

You know that a + b = 2b (library books plus textbooks equals twice number of textbooks)

You know that b + c = 3a (textbooks plus telephone books equals three times number of library books)

Take equation #2 a+b=2b

Subtract b from each side

a=b The number of library books equals the number of textbooks

Take equation #3 b+c=3a Substitute a for b since you know now from equation #2 that a=b Now you have a+c=3a

Subtract a from each side c=2a

Now, go to equation #1 a+b+c=36

You know a=b

You know c=2a

substitute

a + a + 2a = 36

Combine like terms and divide

4a = 36 a= 9

Again, you know a = b and c= 2a therefore a=9, b=9, c=18

9 library books

9 text books

18 telephone books

## Answer This Question

## Related Questions

- math - kyle had 36 books in hislocker. some were library books, some were ...
- math - kyle had 36 books in hislocker. some were library books, some were ...
- Math, Please help :/ - Kyle had 36 books in his locker. Some were library books...
- math - MEghan had 36 books in her locker. Some were library books, text books ...
- math - the library has a total collection of 2630 books. the number of non-...
- math - the library has a total collection of 2630 books. the number of non-...
- math - the library has a total collection of 2630 books. the number of non-...
- English - 1. We should not scribble in books in the library. 2. We should not ...
- algebra - John has 36 books in his locker. He has text books,library books, and ...
- whole number - At the end of the year, a library reported 32 books lost or ...

More Related Questions