A scientist is studying global warming. She wants to change her average temperature
calculations from Celsius to Fahrenheit. The average temperature that she recorded for the Earth
last year was 15 degrees Celsius. The formula for changing from Celsius to Fahrenheit is the
quantity of the Celsius temperature times nine-fifths plus 32 degrees. According to the scientist’s
data, what was the average temperature, in Fahrenheit, of the Earth last year?

Question

A scientist is studying global warming. She wants to change her average temperature 
calculations from Celsius to Fahrenheit. The average temperature that she recorded for the Earth 
last year was 15 degrees Celsius. The formula for changing from Celsius to Fahrenheit is the 
quantity of the Celsius temperature times nine-fifths plus 32 degrees. According to the scientist’s 
data, what was the average temperature, in Fahrenheit, of the Earth last year?