Answer:
20 minutes on the stationary bike
10 minutes on the treadmill
Step-by-step explanation:
x = minutes on bike
y = minutes on treadmill
x + y = 30
12x + 15y = 390
x = 30-y
12(30-y) + 15y = 390
360 - 12y + 15y = 390
3y = 30
y = 10
x + 10 = 30
x = 20
Answer:







you're welcome I think I don't really know whether I'm finding x or y or yx
Answer:
Answer is -759/5
Step-by-step explanation:
To find the sum of a finite geometric series, use the formula,
Sn= a1-a1r^n/ 1-r
where n is the number of terms, a1 is the first term and r is the common ratio .
common ratio = a2/a1
S8=3-3(-2/3)8 / 1-(-2/3)
S8 = 3-(-2)8/ 1+ 2/3
S8= 3-256/ 3+2/3
S8= -253/5/3
S8= -253*3/5
S8= -759/5