You can use this one app it’s called Cymath it’s really helpful with these types of problems,
He would have 21 before he bought the 10 stamp because 31-10=21
Answer:
π/90 or 0.0035 units
Step-by-step explanation:
equation: <em>length of the arc = ∠of the angle/360 * circumference</em>
Substitute: <em>S = 0.4/360 * 10π</em> --> C = 2πr
Simplify: S = 1/900 * 10π
Simplify: S = π/90 ≈ 0.003489 units
Answer: Negative
If the same negative number is multiplied to each side of a true inequality, then the inequality sign flips to make the new inequality true as well
Example:
Take 1 < 5 and multiply both sides by -2 and we get -2 > -10. The "less than" sign flips to "greater than" since -2 < -10 is false. The value of -10 is further to the left of -2 so -10 is smaller in value. The negative basically takes the complete opposite which is why the flip must happen.
This sign flip rule does not happen if you multiply both sides by a positive number.
I'm going to divide number one to 6 parts
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because to make the denominator to 100, you need to multiply 10 by 10 which is 100.
and because you multiply 10, you also have to multiply the numerator by 10.
EXAMPLES:

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