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:
you start counting from left to right
when you want to calculate the difference you have to choose two numbers that are next to each other and subtract second one from first one and because the different between every 2 numbers in order are the same numbers we call it a common difference.
Step-by-step explanation:
for example for 4 :
1. we can choose two numbers next to each other like 1 and 1.1
2. subtract second from first like 1.1 - 1 = 0.1
3. 1.1 + 0.1 = 1.2
1.2 + 0.1 = 1.3
and ...
so the common difference is 0.1
Answer:
235
Step-by-step explanation:
42+1
43
3 times 43
129
129 times 2
258
258-23
235
Answer:
simplified 
Step-by-step explanation:
To turn a mixed number into a fraction :
3 x 4 =12 +2 =14 that will be your numerator (top number on a fraction)
and 4 will be your demoninator (bottom number)
Answer:
B. 2x – 1 = 13 and x = 7
Step-by-step explanation:
We are given 4 equations and a solution for each. We have to tell which of the given solution satisfies the given equation.
Option A.
2x -1 = 13 and x = 6
Using this value in the equation, we get:
2(6) -1 = 13
12 - 1 = 13
11 = 13, which is not true. Hence this option is not valid
Option B.
2x - 1 = 13 and x = 7
Using the value in the equation, we get:
2(7) - 1 =13
14 - 1 =13
13 = 13, which is true. Hence this option is valid.
Option C.
2x + 1 =13 and x = 7
Using the value in the equation, we get:
2(7) + 1 = 13
15 = 13, which is not true. So this option is not valid
Option D.
2x - 1 = 13 and x = 11
Using this value in the equation, we get:
2(11) - 1 = 13
21 = 13, which is not true. Hence this option is not valid.
