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: 2 3/4 > 2.68 is correct (only)
Step-by-step explanation: 2 3/4 = 2.75, and 2.75 is greater than 2.68
The rest are incorrect. 7.895 * 10^2 (100) = 789.5, and 5.43 * 10^3 (1000) = 5430. So 789.5 > 5430 is false.
Sqrt(63) = 7.93, and 7.93 > 8.11 is false.
Absolute values ( | | ) mean that no matter if it is negative or positive, it will become positive (unless the negative sign is outside the absolute value). 1.5 > 3.2 is false, and even without the absolute value, -1.5 is still less than 3.2
Answer:
1/2 is the fractional part of cookie which was eaten by Dan.
Step-by-step explanation:
Dan has 2 1/2 cookies and ate 1/2, so we can just subtract the 2 1/2-1/2
which cancels out the 1/2, which is the fractional part.
He has 2 cookies left.
