Answer:
156 students
Step-by-step explanation:
To find how many students are in choir this year, multiply 120 by 1.3
120(1.3)
= 156
So, this year, 156 students are taking choir
Answer:
If your trying to solve for a, I believe this is the answer: a = 4b / (2 - c)
Step-by-step explanation:
2a - b = ac + 3b
First you want to group by like terms, so for "b" you are going to add "b" to both sides so that it cancels out on the left side and you now have all of your "b's" on the right.
2a = ac + 4b
next, you want to get the a's on the left side so you are going to subtract "ac"
2a - ac = 4b
Now, you need to factor the "a" out, and since its the greatest common factor among the "2a - ac" you are left with "a(2 - c)"
a(2 - c) = 4b
Finally divide both sides by "(2 - c)"
a = 4b / (2 - c)
and that's your answer
Answer:
a) 69.5 b)72.1 c)74.7
Step-by-step explanation:
a)Someone born in 1950 has life expectancy=68.2 yrs while 1970=70.8 yrs
to find life expectancy of someone born in 1960 we can interpolate to find the results like this:
(68.2+70.8)/2 =69.5 because 1960 is exactly in between 1950 and 1970
Now we can see the trend like this :
68.2,69.5,70.8 and common difference is 1.3
b) adding 1.3 to 70.8 we can get life expectancy for someone born i 1980 and that is 72.1
c) adding two times 1.3 life expectancy of someone born in 2000 is 74.7 as year gap is 2
Generally it is said that interpolation is more accurate and extrapolation can have errors but in our present case i'm more confident about b and c as the series is simple but it too depends on a to find the accurate common difference so if there is some errror in a we too have error chances in b and c so they are interrelated.
If you rounded it it would be 4.6