Ingrid types 3 pages in the same amount of time that tanya types 4.5 pages. if the grid and tanya start typing at the same time how many pages will tanya have typed when ingrid has typed 11 pages ?

The ratio here is 3:4.5
11 is not divisible by 3 so we can divide the ratio by 3 to find out how many pages Tanya types in the same time as Ingrid types one.

3:4.5 ÷3 = 1:1.5

Now we have to multiply 1.5 by 11 as this is how many Ingrid has done. 11x1.5= 16.5
so Tanya will have typed 16.5 pages