Posted by **rebeca** on Tuesday, October 2, 2007 at 12:32pm.

alter working 4 hours, frank has made 21 machine parts.at the same rate how many parts can he make in 7 hours? 4(21)/7,7(21),7(21)/4,7(4)/21,7(4)(21)?

- math -
**Ms. Sue**, Tuesday, October 2, 2007 at 12:34pm
Please post your answer and we'll be glad to check it.

- math -
**rebeca**, Tuesday, October 2, 2007 at 1:09pm
i choose a)4(21)/7

- math -
**DrBob222**, Tuesday, October 2, 2007 at 12:36pm
Look at dimensional analysis.

21 parts/4 hrs x ?hrs = ?parts.

- math -
**Ms. Sue**, Tuesday, October 2, 2007 at 1:13pm
How can a) be the right answer? 4(21)/7 = 12. The problem has stated that he made 21 parts in 4 hours. How can he make fewer parts in more hours?

Please try again.

Hint: you could set up a proportion:

4 is to 21 as 7 is to x

- math -
**rebeca**, Tuesday, October 2, 2007 at 1:23pm
d)7(4)/21

- math -
**Ms. Sue**, Tuesday, October 2, 2007 at 1:27pm
7(4)/21.

Do the math. Does the answer make sense?

## Answer this Question

## Related Questions

- math - After working 4 hours frank made 21 machine parts. it's the same rate how...
- math - After working 4 hours, Frank has made 21 machine parts. At the same rate...
- Mathematics - A machine takes 4.2 hours to make 7 parts. At that rate, how many ...
- Math - Please help! It says- A machine takes 4.0 hours to make 8 parts. At that ...
- Math - Find a unit rate for number of parts manufactured per hour if 1628 parts ...
- Algebra - find the unit rate for number of parts manufactured per hour if 1630 ...
- math - A worker in an assembly line take 2 hours to produce 120 parts. At that ...
- Math - Jocelyn made a spinner If Jocelyn spins only one time what is the ...
- math - A machine has four components, A, B, C, and D, set up in such a manner ...
- math - A new machine that deposits cement for a road requires 13 hours to ...

More Related Questions