You need to perform the multiplication` t*(3/4)` for `t = 8/9` , hence, you need to substitute `8/9` for t, such that:

`(8/9)*(3/4) = (8*3)/(9*4)`

You may write ` 8 = 2*4` and `9 = 3*3` such that:

`(8*3)/(9*4) = (2*3*4)/(3*3*4)`

Reducing duplicate factors yields:

`(8*3)/(9*4) = 2/3`

**Hence, performing the multiplication `t*(3/4), t = 8/9,` yields **`(8*3)/(9*4) = 2/3.`