Answer:
1050
Explanation:
We can use a ratio to solve
First find how many jam
210 - 189 =21
We want to find how many jam for 10500 printed
21 jam x jam
----------- = ----------------
210 printed 10500 printed
Using cross products
21 * 10500 = 210x
Divide each side by 210
21*10500/210 =x
1050=x