The ratio of red to green is 5:6 which means that for every 5 red cars, there are 6 green cars
The ratio of green to blue is 3:10 telling us that for every 3 green cars, there are 10 blue cars.
The ratio 3:10 is equivalent to 6:20 after we multiply both parts by 2. This now says that for every 6 green cars, there are 20 blue cars.
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Let's say we had 5 red cars, 6 green cars and 20 blue cars Based on that info, we know that the ratio of red to green is 5:6 And the ratio of green to blue is 6:20 which reduces to 3:10
We don't reduce 6:20 to 3:10 however, since that would change the green count from 6 to 3. We want to keep the green count at 6.
So because there are 5 red cars, 6 green cars, and 20 blue cars in this example, and this example points to the proper ratios mentioned earlier, this means that the final answer is 5:6:20. This ratio cannot be reduced or simplified as there are no common factors (other than 1) for 5, 6, and 20.
The first thing that he has to do is take that "minus" sign through the parentheses containing the second polynomial. Some students find it helpful to put a " 1 " in front of the parentheses, to help them keep track of the minus sign. Here's what the subtraction looks like, when working horizontally/