Answer:
The 15th day
Step-by-step explanation:
Violin Lessons - 3, 6, 9, 12, 15
Singing Lessons - 5, 10, 15
Landen will have violin and singing lessons on the fifteenth day.
Hope this helped! :)
or d = 3.61
6.6a+6b-7.1
Table, Formula
0.0003625
:) Hope that helps :)