Malik recorded the grade-level and instrument of everyone in the middle school School of Rock below.
Seventh Grade Students
Instrument # of Students
Guitar 8
Bass 2
Drums 13
Keyboard 3
Eighth Grade Students
Instrument # of Students
Guitar 8
Bass 11
Drums 7
Keyboard 8

Based on these results, express the probability that a student chosen at random will play the guitar as a decimal to the nearest hundredth.