A rate is a special ratio in which the two terms are in different units. For example, if a 12-ounce can of corn costs 69¢, the rate is 69¢ for 12 ounces. ... When rates are expressed as a quantity of 1, such as 2 feet per second or 5 miles per hour, they are called unit rates.
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To make it easier, lets say Justin = J, Eva = E, and Emma = M. Then, J = E + 7.50 M = J -12 J + E + M = 63 You can substitute for M in the third equation using the second equation, and you get: J + E + J - 12 = 63 Clean it up a little bit and you get: 2J + E = 75 You know J = E + 7.50, so substitute that for J and you get: 2(E + 7.50) + E = 75 2E + 15 + E = 75 3E + 15 = 75 3E = 60 E = 20 ; meaning that Eva has $20. Justin has $7.50 more than Eva, so he has $27.50. Emma has $12 less than Justin, so Emma has $15.50. Double check your answer by making sure they all add up to 63, which they do.
Answer:
To find the scale factor, we simply create a ratio of the lengths of two corresponding sides of two polygons. If the ratio is the same for all corresponding sides, then this is called the scale factor and the polygons are similar.
The disadvantage would be well, u know how u can divide a even number (not prime unless it's 2) into equal parts by putting the first segment in the middle then the next two in the middle of those? Well, u can't do that with a prime number because u can't divide any prime number like that. It's the best I can explain this concept. I'm pretty sure I'm right, but it's just hard to explain.
