A)
Let x represent the cost of 1 student, and y the cost of 1 teacher.
B)
In the first group, there's 25 students and 2 teachers. Their total cost is $97.50
So 25x + 2y = 97.50
In the second group, there's 32 students and 3 teachers. Their total cost is $127
So 32x + 3y = 127
We get the following system of equations:
25x + 2y = 97.50 (1)
32x + 3y = 127 (2)
C)
25x + 2y = 97.50 (1)
32x + 3y = 127 (2)
In equation (1)
25x + 2y = 97.50
25x + 2y - 2y = 97.50 - 2y
25x = 97.50 - 2y
25x / 25 = 97.50/25 - 2y/25
x = 3.9 - (2/25)y
In equation (2), let's replace x by its algebraic value
32x + 3y = 127
32(-2/25y + 3.9) + 3y = 127
11/25y + 124.8 = 127
11/25y + 124.8 - 124.8 = 127 - 124.8
11/25y = 2.2
(11/25y) / (11/25) = 2.2 / (11/25)
y = 5
x = -2/25y + 3.9
x = -2/25 * 5 + 3.9
x = 3.5
So the cost of each student is $3.5, and the cost of each teacher is $5.
Hope this helps! :)
Answer:

Step-by-step explanation:
A quadratic equation in one variable given by the general expression:

Where:

The roots of this equation can be found using the quadratic formula, which is given by:

So:

As you can see, in this case:

Using the quadratic formula:

Therefore, the answer is:

She has 3 children. One children is 17, the other is 19 and the other one is 23
Answer:
30mph
Step-by-step explanation:
be smart
For compound interest, the formula is given below:
Amount = 
Here, P = 18,800
n = 2
r = 13/100
So, Amount = 

= 18,800 × 1.2769
= 24005.72
Compound Interest = Amount - Principal
Compound Interest = 24005.72 - 18800
= 5205.72
Hence, the compound interest for Rs.18,800, calculated for 2 years at 13% rate of interest compounded annually is Rs.5205.72.