Let XXX and YYY be the following sets: X = \{9, 25\}X={9,25}X, equals, left brace, 9, comma, 25, right brace Y = \{1, 4, 9,16,25
Dmitry_Shevchenko [17]
Answer:
The answer is "
"
Step-by-step explanation:
Given value:

When we subtract set X - Y it means, that it will give only, that value which is not available on the set Y.

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
__________________________________________________________
I just realized that there can't be a negative amount of children, so I'm sorry if these results are all wrong.
Hello,
Here is the demonstration in the book Person Guide to Mathematic by Khattar Dinesh.
Let's assume
P=cos(a)*cos(2a)*cos(3a)*....*cos(998a)*cos(999a)
Q=sin(a)*sin(2a)*sin(3a)*....*sin(998a)*sin(999a)
As sin x *cos x=sin (2x) /2
P*Q=1/2*sin(2a)*1/2sin(4a)*1/2*sin(6a)*....
*1/2* sin(2*998a)*1/2*sin(2*999a) (there are 999 factors)
= 1/(2^999) * sin(2a)*sin(4a)*...
*sin(998a)*sin(1000a)*sin(1002a)*....*sin(1996a)*sin(1998a)
as sin(x)=-sin(2pi-x) and 2pi=1999a
sin(1000a)=-sin(2pi-1000a)=-sin(1999a-1000a)=-sin(999a)
sin(1002a)=-sin(2pi-1002a)=-sin(1999a-1002a)=-sin(997a)
...
sin(1996a)=-sin(2pi-1996a)=-sin(1999a-1996a)=-sin(3a)
sin(1998a)=-sin(2pi-1998a)=-sin(1999a-1998a)=-sin(a)
So sin(2a)*sin(4a)*...
*sin(998a)*sin(1000a)*sin(1002a)*....*sin(1996a)*sin(1998a)
= sin(a)*sin(2a)*sin(3a)*....*sin(998)*sin(999) since there are 500 sign "-".
Thus
P*Q=1/2^999*Q or Q!=0 then
P=1/(2^999)
Answer:
It is going 84.12s = 1 minute and 24.12 seconds to fill the tank.
Step-by-step explanation:
The filling time of a gas tank can be given by a first order function in this format:

In which
is the current amount of fuel in the tank(in L),
is the volume of the tank(in L),
is the discharge rate of the tank(in L/s) and t is the time in seconds.
Finding the values of the parameters:
The tank is completly empty, so
.
The volume of the tank is 14 gallons. However, the problem states that the volume of the tank is measured in liters.
Each gallon has 3.78L.
So 
The discharge rate for the gas is 38.0 l/min. However, the problem states that the discharge rate is in L/s. So, to find the value of r, we solve the following rule of three.
38 L - 60s
r L - 1s



Solving the equation:





It is going 84.12s = 1 minute and 24.12 seconds to fill the tank.
Given:
In given Δ RST,
RS = 9, ST = 8 and ∠S = 110°
To find the value of another side RT (s).
Formula
By cosine law we get,

Now,
Putting,
b=9, c=8, A = 110° and a=s we get,

or, 
or, 
or, 
or, 
or, 
Hence,
The value of s is 14. Option C.