Meaning of 'doubled'

[jorien]

Test No. incompl/inter-3 "If you tend to forget", question 6

If you had bought a house about thirty years ago you would certainly find that it had considerably ......... in value.

(a) increased
(b) heightened
(c) developed
(d) doubled

Test No. incompl/inter-3 "If you tend to forget", answer 6

If you had bought a house about thirty years ago you would certainly find that it had considerably increased in value.

Correct answer: (a) increased

Your answer was: incorrect
If you had bought a house about thirty years ago you would certainly find that it had considerably doubled in value.
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What does the sentence mean when you use the word "double"

[Alan]

This means twice as valuable but you cannot qualify this with considerably.
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English as a Second Language
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