Answer: 12
Step-by-step explanation:
You can multiply by 12 because to get rid of the fractions all terms should be divided by the LCM (ie the smallest multiple that is exactly divisible by 2, 4 and 3)
Multiples of 3 = 3, 6, 9, 12
Multiples of 4 = 4, 8, 12, 16
Multiples of 2 = 2, 4, 6, 8, 10, 12
Therefore the fractions should be multiplied by 12
This is the answer for your problem
Answer:

The world population at the beginning of 2019 will be of 7.45 billion people.
Step-by-step explanation:
The world population can be modeled by the following equation.

In which Q(t) is the population in t years after 1980, in billions, Q(0) is the initial population and r is the growth rate.
The world population at the beginning of 1980 was 4.5 billion. Assuming that the population continued to grow at the rate of approximately 1.3%/year.
This means that 
So


What will the world population be at the beginning of 2019 ?
2019 - 1980 = 39. So this is Q(39).


The world population at the beginning of 2019 will be of 7.45 billion people.
Answer:
At 7% $54,000
At 9% $156,000
Step-by-step explanation:
Let x be the amount invested at 7%, Then 2x + 48000 will be the amount invested at 9%
We know that:
7% = 0.07 & 9% = 0.09
So we can write the interest equation as follows:
0.07x + 0.09 (2x + 48000) = 17820
0.07x + 0.18x + 4320 = 17820
0.25x + 4320 = 17820
Subtracting 4320 from both sides of the equation we get:
0.25x = 17820 - 4320
0.25x = 13500
Dividing both sides of the equation by 0.25 we get:
x = 13500 / 0.25
x = $54,000 invested at 7%
&
2 x 54000 + 48000
= $156,000 invested at 9%
Hence the amount invested at 7% is $54,000.
& the amount invested at 9% is $156,000.
It’s not my answer but I think it’s correct!