Adj-worth

Hi everybody,



Could you please answer the following questions?



http://www.oxfordadvancedlearnersdictionary.com/dictionary/worth



1) Our house is worth about £100000. (1^st entry)

2) Our house is worth £100000. (Is this sentence correct?)



3) He's worth £10 million (4^th entry).

4) He's worth about £10 million.(Is this sentence correct?)



Thank you