SAT Math Practice Question #35815 - SATify | SATify

#35815

functions

exponential

medium

75 sec

The amount of a certain radioactive substance remaining, in grams, is modeled by an exponential function of time, $t$ , in hours. The table shows the amount of the substance remaining at different times.

Time (hours)	Amount (grams)
0	100
1	80
2	64

By what percentage does the amount of the substance decrease each hour?

• Up to 5 characters (6 if negative). Only numbers, decimal (.), fraction (/), negative (-).
• Fractions must be in lowest terms.
• Mixed numbers must be converted to improper fractions.