Respuesta :
Answer:
(10.5 - 0.75y) hours
Step-by-step explanation:
Number of days in 1 week = 7 .
Number of days in a week Karla sings = y
Number of days Karla plays piano in a week = Number of days in 1 week - Number of days in a week Karla sings
Number of days Karla plays piano in a week = 7 - y
In 1 day Karla sings for = 45 minutes
60 minutes = 1hour
45 minutes = 1/60 * 45 = 3/4 hours = 0.75 hours
In y days time for which Karla sings = y *0.75 hours= 0.75y hours
Time for which Karla plays piano in 1 day = 1.5 hours
Time for which Karla plays piano in (7-y) day = 1.5*(7-y) hours
Total time in hours for which karla sings and plays the piano each week
= 0.75y + 1.5*(7-y)
= 0.75 y + 10.5 - 1.5y
= 10.5 - 0.75y
Thus, total number of hours karla sings and plays the piano each week is 10.5 - 0.75y hours
