Answer:
0.006% of people had a reaction
Explanation:
1,500 tried it -----> 9 had a reaction
9/1,500
Divide both numerator and denominator by 3
3/500
Multiply by 2 to get the fraction out of 1000
6/1000
Divide by 10 to get the fraction out of 100
0.6/100
0.006%
Hope this helps :) Let me know if you have any questions about my answer.