Answer:
-2497
Step-by-step explanation:
Sn=n/2[2a+(n-1)d]
=22/2[2*-40+(22-1)d]
=11(2*-40+(21*-7)
= -2497
I think it's 7.52 and then 8.52
Answer:
2 notebooks are $2.48, 7 notebooks are $8.68
Step-by-step explanation:
Unit rate is 1.24
1.24x2= $2.48
1.24x7= $8.68
Answer:
Step-by-step explanation:
The acute angles of a right-angled triangle other than the right angle always add up to 90 degrees.
<u>So, we get:</u>
(48 - x) + (3x - 10) = 90
48 - x + 3x - 10 = 90
-x + 3x - 10 + 48 = 90
2x + 38 = 90
2x = 90 - 38
2x = 52
Divide both sides by 2
x = 52 / 2
x = 26
![\rule[225]{225}{2}](https://tex.z-dn.net/?f=%5Crule%5B225%5D%7B225%7D%7B2%7D)
Hope this helped!
<h3>~AH1807</h3>
Answer:
4
Step-by-step explanation:
Every year, the world grows by 1.1%. Converting to a decimal, we can divide by 100 to get 1.1% = 0.011. This means that the world grows by 0.011 exponentially each year. To put this into an expression, we can add 1 to our percentage to get 1.011. This represents 1 = 100% (the original population) and the growth of 1.1% = 0.011. We multiply the rate including the growth by the population to get the population after one year. After the first year, we have
population * 1.011 as the new population after one year. We do that for every year, so the second year's population is population*(1.011)*(1.011) and so on. If x represents the amount of years, then the population can be represented as
(original population)*1.011ˣ
Therefore, to get from 7 billion to 7.31 billion, we have
7 billion * 1.011ˣ = 7.31 billion
divide both sides by 7 billion to relatively isolate the x
1.011ˣ = 7.31/7
Another way of writing this is
log (base 1.011) (7.31/7) = x
≈ 3.96
Rounding to the nearest whole number, we get 4 as our answer
