One Chemistry Problem

If you are able, please explain to me how to work out this problem:

What is the maximum number of grams of phosphorus hydride, PH3, that can be formed when 12.4 grams of phosphorus, P4, reacts with 1 gram of hydrogen, H2, to form PH3?

Your help is much appreciated, thank you!

Write the balanced equation first.
P4 + 6H2 ---> 4PH3

You have to find the limiting reagent:

Try P4 first.
12.4g P4 x (1 mol P4 / 123.9g P4) x (4 mol PH3 / 1 mol P4) x (34.0g PH3 / 1 mol PH3) = 13.6g PH3

Now try H2.
1g H2 x (1 mol H2/ 2g H2) x (4 mol PH3 / 6 mol H2) x (34.0g PH3 / 1 mol PH3) = 11.3g PH3

Because H2 is the limiting reagent, the answer would be 11.3g PH3

First, write the balanced chemical equation:
P4 + H2 ---> PH3 becomes
P4 + 6H2 ---> 4PH3

Now use the equation and mole ratio to get the answer:
12.4g P4 x (1 mol P4 / 123.9g P4) x (4 mol PH3 / 1 mol P4) x (34.0g PH3 / 1 mol PH3)

= 13.6 grams of PH3 is the most we can produce with only 12.4 grams of P4.

Does the mole ratio make sense here?