Bunuel
In a hot dog eating contest, two participants, Leo and Marco, competed for the same amount of time. During that time, Leo ate 36 hot dogs, and Marco ate 30 hot dogs. What was Marco’s average rate, in hot dogs per hour, during that time?
(1) Marco’s average rate was 6 hot dogs per hour less than Leo’s.
(2) In the first 20 minutes, Leo ate 12 hot dogs.
See, it is already mentioned that they are competing for same time.
In equation 1, we come to conclusion if Leo eat at rate of L dogs per hour, then marco would eat in L-6 dogs. now, we know
Number of Dog Marco Eat / Rate of eating dogs by marco = Number of dogs eaten by Leo / Rate of eating by Marco
so from here we can find L and can find Marco average rate too. So (1) alone is suffecient
Now for equation 2,
it is written than Leo eat 12 dogs in 20 mins, which means the ratio of dog eaten by marco and leo is same as dogs eaten in 20 minutes by them.
So if leo eats 36 dogs in same time as Marco eat 30, it means if leo eats 12, marco would eat 10. and now we know how many dogs marco ate in 20 minutes and so we know the average rate too. So (2) is sufficient.