# How can you determine Mass / kg from the attached table

I spent the last two hours trying to figure out part D and I can't get my head around it... Part D has the formula mass/kg = Mass/kg = C / ΣC I'd imagine "C" is the number of C section of the table. Does anyone know how can I calculate that number?

• $D$ seems to be the fraction of total mass, e.g. $5.28 / 29.92 \approx 0.176$ (which means $17.6\%$ of the total mass) – ccorn Apr 11 '14 at 18:23

for CO2: take $\dfrac{5.28(\text{Mass of CO2})}{29.92}$ = .17647
for CO: take $\dfrac{.84(\text{Mass of CO})}{29.92}$ = 0.02807, etc.
If there was confusion about what was in the denominator, $\Sigma C$ means the sum of elements in column C. Where in this case $\Sigma C = 5.28+.84+23.8$ = 29.92