Answer:
- after week 7: 4374 pennies
- 486 pennies: after week 5
Step-by-step explanation:
The sequence values have a first term of 6 and a common ratio of 3, so can be described by the formula ...
an = 6·3^(n-1)
This can be rearranged to ...
an = 2·3^n
__
When n=7, the value is ...
a7 = 2·3^7 = 4374 . . . . pennies saved after 7 weeks
__
To find when there are 486 pennies saved, we can solve the equation ...
486 = 2·3^n
243 = 3^n
log(243) = n·log(3) . . . . . . . take the logarithm
log(243)/log(3) = n = 5 . . . . divide by the coefficient of n
Tabitha will have saved 486 pennies after 5 weeks.
Let's say that the unknown value here is c. Although we are given two points on the line, it is only necessary to use one as there is only one unknown value, so let's say we choose the point (6, -12) and substitute this into the equation:
-12 = 1(6) - c
-12 - 6 = -c
-18 = -c
c = 18
Thus the equation for the line is y = 1x - 18
0.4kg per week. so 0.4kg x 6 weeks is 2.4kgs
Answer:
30%
Step-by-step explanation:
the percent of 24 of 80 is 30% so they rasid the price 30% percent of 80
6th grader here sorry if wrong