Sentence Correction

Due to the decrease in active lifestyle and the increase in high fat diets, the adult ovesity rate in the united kingdom increased by more than threefold from 1980-2006.

a. same
b. increased by more than triple
c. increased more than three times
d. more than tripled
e. had mroe than tripled

QA is D but what is wrong with C. I have no idea the relationship between double and two times or twice. Where can I go to learn more about this?

In SC the one rule is to avoid wordy sentence.
If you know a suitable replacement for group of words you should use that.

Here "increased by more than threefold" can be replaced by " more than tripled"

You can find explaination in MGAT SC or even in Princeton review.

is there a difference or a certain rule I don't know. IS there a difference between double and twice , three times and triple?

The problem with "more than three times" is that it's ambiguous - it could refer to the amount of the increase or it could refer to how often adult obesity increased.

For example:

"Last month my weight increased more than three times"

could mean:

"Last month my weight increased on the 4th, 7th, 9th and 11th".

so is there a difference between double and twice? I wonder if there is a hard rue for that!

hello friend

you have sentence correction bible, havent you, could you please, email it to me, or give a link to its website. I am in Vietnam and so, can not buy the book, pls email to [email protected]
thank you very much.

tripple" mean it is now 30 person, before 10 person

more than 3 time mean, it is increase 4 times, but may be only 14 person, before is 10 person,

hope you get it

Thang,