What's the meaning of "as many as" in these contexts?

Question

I watched this video by Vox titled, "Why there are twice as many solar jobs as coal jobs?" I would never understand what does the title mean if I don't watch the video. I mean, I know that if you say "X is as many as Y" means that X = Y. But when X is added after many, making it "as many X as Y" or "twice as many X as Y", what do they mean?

Here are some possible usages of the phrase:

1. There are twice as many blue-collar workers as white-collar workers in this room.
2. I bought as many pears as apples which you bought.
3. I can see as many adults as teenagers in that bus.

Answer 1

"There are as many X as Y", that means that the number of X's is the same as the number of Y's. For example, "There are as many cell phones as people in our house" means that the number of cell phones is equal to the number of people.

"There are Z times as many X as Y" means that the number of X's is equal to Z times the number of Y's. For example, "There are three times as many cell phones as people in our house" means that the number of cell phones is equal to three times the number of people. If there are 4 people then there are 12 cell phones. "Twice" is short for "two times".

Note such numbers aren't necessarily exact. If there are 60 dogs and 31 cats, I might say "there are twice as many dogs as cats". We tend to accept inexactness more in the bigger number. "Twice as many dogs as cats" would be considered true if there were 70 dogs and 30 cats, but more questionable if there were 50 dogs and 30 cats.