Question

it's reported that most of the familie‘s income is 3 times or more what it was 3 years ago

为什么用what 而不是than

Answer 1

这里的what引导的从句是跟在3 times后面的，"or more"是个补充说明，所以不是比较状语从句，不能用than,
3 times what it was three years ago“是3年前的3倍”。倍数的表达方式：times + 名词+ of,比如：His room is twice the size of mine.他的房间有我的2倍大，= his room is twice as big as mine.
例句中what 引导名词性从句，代替的就是上面我说的times后面跟的名词。

Answer 2

据报导大多数家庭的收入是三年前的三倍或者更多，what指的就是收入的多少

Answer 3

it was 后面缺什么，缺“什么”吧，那就用what 呗