Answer: 8 batches
explanation: 5 1/3 divided by 2/3 equals 8. To find out how many batches were made, you need to divide the total amount used by the amount needed for one batch.
P=Ae^kt
225 = 210 * e^(k*(1990-1980)
225/210=e^10k ln(225/210)=10k
k=ln(225/210)/10=0.0069
P = 210*e^(0.0069t)
for 2000 ===> t = 2000-1980=20
P = 210*e^(0.0069*20)
P=241.0749=241
Answer: exact form: y= -23/4
Step-by-step explanation: move all the terms that doesn’t contain “y” to the right side and solve.