Answer:
15
Step-by-step explanation:
you have to multiply first because of the order of operations, so 2 × 3 = 6, and 6 + 9 = 15
x = number of 1-cent stamps
y = number of 8-cent stamps
z = number of 12-cent stamps
We have 31 stamps all together, so x+y+z = 31.
"I have 4 more 1-cent stamps than 8-cent stamps" means we have the equation x = y+8. Whatever y is, add 8 to it to get x. Solve for y to get y = x-8.
You also have "twice as many one cent stamps as 12 cent stamps", so x = 2z. Solving for z gets you z = 0.5x
-------------
x+y+z = 31
x+x-8+z = 31 ... y replaced with x-8
x+x-8+0.5x = 31 ... plug in z = 0.5x
2.5x-8 = 31
2.5x = 31+8
2.5x = 39
x = 39/2.5
x = 15.6
Your teacher made a typo somewhere because we should get a positive whole number result for x (since x is a count of how many 1-cent stamps we have).
Answer:
C. 0.006 g/cm³
Step-by-step explanation:
As the units tell you, density is the ratio of mass to volume. The volume of the container is found from ...
V = πr²h = π(10 cm)²(25 cm) = 2500π cm³
Then the density is ...
ρ = (50 g)/(2500π cm³) = 1/(50π) g/cm³
ρ ≈ 0.006 g/cm³
_____
<em>Comment on the problem</em>
The "liquid" has about the same density as air pressurized to 75 psi.
(x+2)(x-16)
A = X
B= 2
C= X
D= -16
