00:01
Okay, so what does it mean that y is directly proportional to x? well, what this means is as y increases, x will also increase at the same time, or as y decreases, x will also decrease.
00:13
So, if they were always equal to a constant k, which is a fixed number, would y and x have to be multiplied or divided to always increase and decrease together? well, they'd have to be divided, right? equivalent fractions as the numerator increases, the denominator has to also increase to equal the same constant.
00:32
So then if an item sales for $140, x is the sales tax, so 148, excuse me, all over the sales tax is $10 .22.
00:49
Would my constant be, we'll just divide in these two numbers, 10 .22 divided by 148, the retail price.
00:58
That is going to be approximately to four decimal places.
01:02
0 .06905.
01:06
Does that 5 end up at 0 .0 .691...