This is a quadratic function:
f(x)=ax²+bx+c
We have three points:
(0 , 77.6)
(5 , 78)
(10 , 78.6)
Then, we make the function wiht these points:
(0 , 77.6)
x=0
f(x)=77.6
a(0)²+b(0)+c=77.6
c=77.6
(5 , 78)
a(5)²+b(5)+77.6=78
25a+5b=78-77.6
25a+5b=0.4 (1)
(10 , 78.6)
a(10)²+b(10)+77.6=78.6
100a+10b=78.6-77.6
100a+10b=1 (2)
With the equations (1) and (2) we have a system of equations:
100a+10b=1
25a + 5b=0.4
We solve this system of equations by method of elimination.
100a+10b=1
-4(25a+5b=0.4)
-----------------------------
-10b=-0.6 ⇒ b=-0.6/-10=0.06
100a+10b=1
-2(25a+5b=0.4)
----------------------------
50a = 0.2 ⇒ a=0.2/50=0.004
We have a, b and c:
a=0.004
b=0.06
c=77.6
Therefore, the quadratic funtion is:
f(x)=0.004x²+0.06x+77.6
x=year of the beginning of the interval - 1980
The life expectancy for females born between 1995 and 2000 is when x=1995-1980=15
Therefore:
f(15)=0.004(15)²+0.06(15)+77.6
f(15)=0.004(225)+0.06(15)+77.6
f(15)=79.4
The life expectancy for females born between 2000 and 2005 is when:
x=2000-1980=20
therefore:
f(20)=0.004(20)²+0.06(20)+77.6
f(20)=1.6+1.2+77.6
f(20)=80.4
Answer:
The funtion is:
f(x)=0.004x²+0.06x+77.6
x=year of the beginning of the interval - 1980
The life expectancy for females born between 1995 and 2000 is 79.4 years.
The life expectancy for females born between 2000 and 2005 is 80.4 years.
Answer:
True is the answer GL GL GL
Answer:
15
Step-by-step explanation:
75 - 5(2 · 6)
Multiply inside the parenthesis
75 - 5(12)
Distribute
75 - 60
Subtract
15
Hope this helps :)
Answer:
C , 30 N
Step-by-step explanation:
Answer:
The age of youngest brother is <u>21</u>.
Step-by-step explanation:
Given:
The ages of 3 brothers are represented by consecutive integers.
If the oldest brother's age is decreased by twice the younger brother's age, the result is -19.
Now, to find the age of youngest brother.
Let the age of youngest brother be
Let the age of middle one be .
And the age of oldest brother age be
According to question:
⇒
⇒
Adding on both sides we get:
⇒
Adding 19 on both sides we get:
⇒
Now, getting the age of youngest brother by putting the value of :
⇒
Therefore, the age of youngest brother is 21.