If 102y = 25, then 10-y equals ?
Pick
A) 2/5
B) 1/5
C) 3/5
D) 1/50
E) 1/25
102y = 25   (10y)2 = 52   10y = 5   1/10y = 1/5   10-y = 1/5   Answer is 1/5.
<result>B</result>
If 102y = 25, then 10-y equals ?