Step-by-step explanation:
20a + 158+6c=you will expand the brackets
= so it is 120+60+48
20a+158+6c=120+60+48
20a+ 6c=120+60+48-158
20a+6c=70
20a divide by 20+6c divide by 6 on both side
a + c = 0.58
The desired number is the difference between the number of messages sent by the 16th day and the number sent by the 9th day:
... n = t(16) - t(9)
... n = (40×√16) - (40×√9)
... n = 40×(4 - 3) = 40
40 text messages were sent between the ninth and sixteenth day of the month.
I think 15 are orange and 10 are green
