Let us model this problem with a polynomial function.
Let x = day number (1,2,3,4, ...)
Let y = number of creatures colled on day x.
Because we have 5 data points, we shall use a 4th order polynomial of the form
y = a₁x⁴ + a₂x³ + a₃x² + a₄x + a₅
Substitute x=1,2, ..., 5 into y(x) to obtain the matrix equation
| 1 1 1 1 1 | | a₁ | | 42 |
| 2⁴ 2³ 2² 2¹ 2⁰ | | a₂ | | 26 |
| 3⁴ 3³ 3² 3¹ 3⁰ | | a₃ | = | 61 |
| 4⁴ 4³ 4² 4¹ 4⁰ | | a₄ | | 65 |
| 5⁴ 5³ 5² 5¹ 5⁰ | | a₅ | | 56 |
When this matrix equation is solved in the calculator, we obtain
a₁ = 4.1667
a₂ = -55.3333
a₃ = 253.3333
a₄ = -451.1667
a₅ = 291.0000
Test the solution.
y(1) = 42
y(2) = 26
y(3) = 61
y(4) = 65
y(5) = 56
The average for 5 days is (42+26+61+65+56)/5 = 50.
If Kathy collected 53 creatures instead of 56 on day 5, the average becomes
(42+26+61+65+53)/5 = 49.4.
Now predict values for days 5,7,8.
y(6) = 152
y(7) = 571
y(8) = 1631
Answer:
5.0
Step-by-step explanation:
1÷2=2.5
1=2.50×2
=5.0
Subtract 5 from both sides
a/-8 = 4/7 - 5
simplify 4/7 - 5 to 31/-7
a/-8 = 31/-7
multiply both sides by 8
-a = 31/-7 x 8
simplify 31/7 x 8 to 248/7
-a = 248/7
multiply both sides by -1.
The answer is a = 248/7
The words are the explanations of the steps and the dark bolded words are the work shown for each step.
B=blue
g=green
r=red
2 times as many blue as green
b=2g
3 times as many red as blue
r=3b
subsitute 2g for b
r=3(2g)=6g
r=6g
r+g+b=765
so we subsitute
r=6g
g=g
b=2g
6g+g+2g=765
add like terms
9g=765
divide both sides by 9
g=85
subsitute
b=2b
b=2(85)
b=170
170 blue
It’s d cuz it has 14 of them
