How do you balance these equations?

How do you balance these? (chemical + word equations)
1) butane + oxygen = carbondioxide + water
2) pentane + oxygen = carbondioxide + water
3) hexane + oxgen = '' ''
4) heptane + oxygen = '' ''
5) octane + oxygen = '' ''
6) nonane + oxygen = '' ''...

7) decane + oxygen = '' ''

Thank you!!

2) C5H12 + O2 --- CO2 + H2O
Step 1: You've got 5Cs on the left, so put a 5 in front of C02 on the right
C5H12 + O2 --- 5CO2 + H2O

Step 2: You've got 12 Hs on the left, so you put 6 in front of H2O to make 12 Hs
C5H12 + O2 --- 5CO2 + 6H2O

Step 3: You've got 16 Os (10 from CO2, and 6 from H2O) on the right, so you put 8 on the left in front of O2 to balance it
C5H12 + 8O2 --- 5CO2 + 6H2O

Step 4: Check
on the left: 5Cs, 12Hs, 16Os
on the right: 5Cs, 12Hs, 16Os

3) C6H14 + O2 --- CO2 + H2O
Step 1: You've got 6Cs on the left, so put a 6 in front of C02 on the right
C6H14 + O2 --- 6CO2 + H2O

Step 2: You've got 14 Hs on the left, so you put 7 in front of H2O to make 14 Hs
C6H14 + O2 --- 6CO2 + 7H2O

Step 3: You've got 19 Os (12 from CO2, and 7 from H2O) on the right, so you put 9.5 on the left in front of O2 to balance it
C6H14 + 9.5O2 --- 6CO2 + 7H2O

Now count off, on the left 6Cs, 14Hs, 19Os, on the right, 6Cs, 14Hs, 19Os its balanced. BUT you cant have half a molecule.

Step 4: Double everything so there's no half molecules
2C6H14 + 19O2 --- 12CO2 + 14H2O

Step 5: Check
on the left: 12Cs, 28Hs, 38Os
on the right: 12Cs, 28Hs, 38Os

You get the idea...