If we have 420 books for every 7 shelves and are looking for how many books are on 4 shelves, we need to set up fractional proportions.
We have 7 shelves for every 420 books, so we will have our first fraction like this:
7/420.
We also have 4 shelves for every x books, so our second fraction will be 4/x.
Set these fractions up as an equation.
7/420 = 4/x
To solve for x, we need to cross multiply the numerators of one fraction with the denominators of the other fraction.
In other words, multiply the top number of one fraction by the bottom number of the other question.
It should look like this:
7(x)
420(4)
7(x) = 7x
420(4) = 1680
Set your products up as an equation.
7x = 1680
Now to solve for x, we need to simplify.
Currently, x is being multiplied by 7.
To get x alone, divide 7x by 7.
Remember, what you do to one side of an equation, you must do to the other, so divide 1680 by 7.
7x / 7 = x
1680 / 7 = 240
You are left with:
x = 240.
For every 4 shelves you have 240 books.
I hope this helps!
I would think it is a 90 degree angle, sorry if I’m wrong.
Answer:
3rd option
Step-by-step explanation:
Since the centre of dilatation is at the origin then multiply the coordinates by 
K (- 3, 9 ) → K' (- 3( ), 9( ) ) → K' (- 1, 3 )
L (- 9, 0 ) → L' (- 9( ), 0 ( ) ) → L' (- 3, 0 )
M (2, - 8 ) → M' (2 ( ), - 8 ( ) ) → M' ( 
, - 
)
N (6, 4 ) → N' (6 ( ) , 4 ( ) ) → N' ( 2, 
)
<h2>
The stone fall in air for 7 seconds and fall in water for 5 seconds.</h2>
Step-by-step explanation:
Total distance to sea bed = 127 m
Let the distance traveled in air be s.
Distance traveled in water = 127 - s
Average velocity in air = 16 m/s
Average velocity in water = 3 m/s
Distance traveled in air = Average velocity in air x Time in air
s = 16 x t₁
Distance traveled in water = Average velocity in water x Time in water
127-s = 3 x t₂
We have total time is 12 seconds
That is
t₁ + t₂ = 12
We have
s = 16 x t₁
112 = 16 x t₁
t₁ = 7 s
t₁ + t₂ = 12
7 + t₂ = 12
t₂ = 5 s
The stone fall in air for 7 seconds and fall in water for 5 seconds.
75.6 ft^2
The surface area of a pyramid is always squared. Hope that helps
