Answer:
It would cost $20.27 per student.
Step-by-step explanation:
This is a division problem since is gave a total amount ($1480) and gave you an amount (73) which needs to equal 1480 after multiplying it by something. 1480 / 73 would equal 20.27397... You can round the number to the hundredths which would give you $20.27
Ax + 3 = 7 - bx .....add bx to both sides
ax + bx + 3 = 7 ...subtract 3 from each side
ax + bx = 7 - 3
ax + bx = 4 ....factor out x
x(a + b) = 4 ...divide both sides by (a + b)
x = 4 / (a + b) <==
Answer:
1/12
Step-by-step explanation:
Since these are dependent events, the fractions will vary on the second trial.
First trial 3 green marbles out of a total of 9 marbles. That's a 3/9 chances of the marble being green.
Second trial if you already pulled out a green. 2 green marbles are left with 6 other colors. That makes it a 2/8 odds.
Multiply the fractions and you get 6/72, which simplifies to 1/12.
Cos (a-b) = cos(a)cos(b) + sin(a)sin(b)
cos (a+b) = cos(a)cos(b) - sin(a)sin(b)
so, cos(a-b) - cos(a+b) =
=cos(a)cos(b) + sin(a)sin(b) - [cos(a)cos(b) - sin(a)sin(b)]
=2sin(a)sin(b)