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
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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:
$54.51
Step-by-step explanation:
an easier way to do this is simply by multiplying 47.40x115%, which is 54.51.
another way to do this is by multiplying 47.40x15%, which is 7.11, then you'll have to added to 47.4, which gives you the same answer of 54.51
Answer:
2,7
Step-by-step explanation:
Transitive Property of Equality<span>: If a = b and b = c, then a = c.
This is one of the equivalence </span>properties of equality<span>.
Hence, the answer is C.</span>
