Answer:
180
Step-by-step explanation:
The answer is 2.95 × 10²³ atoms
Atomic mass is 200.59 g.
So, 1 mole has 200.59 g. Let's calculate how many moles have 98.3 g:
1M : 200.59g = x : 98.3g
x = 98.3 g * 1 M : 200.59 g = 0.49 M
To calculate this, we will use Avogadro's number which is the number of units (atoms, molecules) in 1 mole of substance:
6.023 × 10²³ atoms per 1 mole
<span>How many atoms are in 0.49 mole:
</span>6.023 × 10²³ atoms : 1M = x : 0.49M
x = 6.023 × 10²³ atoms : 1M * 0.49M = 2.95 × 10²³ atoms
Answer:
y =
x
Step-by-step explanation:
Given that the quantities vary directly then the equation relating them is
y = kx ← k is the constant of variation
To find k use either of the 2 given points
Using (12, 9), that is x = 12 when y = 9, then
k =
=
= 
y =
x ← equation of variation
Given:
A quadratic function has a line of symmetry at x = –3.5 and a zero at –9.
To find:
The other zero.
Solution:
We know that, the line of symmetry divides the graph of quadratic function in two congruent parts. So, both zeroes are equidistant from the line of symmetry.
It means, line of symmetry passes through the mid point of both zeroes.
Let the other zero be x.

Multiply both sides by 2.

Add 9 on both sides.


Therefore, the other zero of the quadratic function is 2.
In order to solve this, you have to set up a systems of linear equations.
Let's say that children = c and adults = a
30a + 12c = 19,080
a + c = 960
I'm going to show you how to solve this system of linear equations by substitution, the easiest way to solve in my opinion.
a + c = 960
- c - c
---------------------- ⇒ Step 1: Solve for either a or c in either equation.
a = 960 - c
20(960 - c)+ 12c = 19,080
19,200 - 20c + 12c = 19,080
19,200 - 8c = 19,080
- 19,200 - 19,200
---------------------------------- ⇒ Step 2: Substitute in the value you got for a or c
8c = -120 into the opposite equation.
------ ---------
8 8
c = -15
30a + 12(-15) = 19,080
30a - 180 = 19,080
+ 180 + 180
-------------------------------
30a = 19,260
------- -----------
30 30
a = 642
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I just realized that there can't be a negative amount of children, so I'm sorry if these results are all wrong.