If it rained on 3 days out of 20 days, on what percent of the days did it rain

For what values of b will f(x)= logbx be a decreasing function? (16 )

Which expressions are equivalent to -6 + 3m

Tim's phone service charges $26.39 plus an additional $0.21 for each text message sent per month. if tim's phone bill was $31.64, which equation could be used to find how many text messages, x, tim sent last month?