Information Given: She has 12 groups of sheep, 3 groups of cows and 2 groups of pigs. Question asks: There are 150 more sheep than pigs. How many cows has she got?
They figured 150 more sheep than pigs from 2 pigs X 75 sheep=150 lambs of 12 groups of sheep.
150 lambs/3 groups of cows=50 cows.
She has 50 cows from 3 groups of cows.
17 tens can be said as 17 x 10
So 17 x 10 is 170
170 is in standard form