Use the table to estimate how long it took Stella Pajunas to type 100 words

# of words: 36 72 108 144 180 216
# of sec: 10 20 30 40 50 60

Its a nice linear line, so no statistical estimation technique required.
For every 10 seconds, Stella can type 36 words. So 36 is to 10 as 100 is to X. That is (36/10)=(100/X). solve for X