My dad heard this story on the radio. At Duke University, two students had received A’s in chemistry all semester. But on the ni
ght before the final exam, they were partying in another state and didn’t get back to Duke until it was over. Their excuse to the professor was that they had a flat tire, and they asked if they could take a make-up test. The professor agreed, wrote out a test and sent the two to separate rooms to take it. The first question (on one side of the paper) was worth 5 points, and they answered it easily. Then they flipped the paper over and found the second question, worth 95 points: ‘Which tire was it?’ What was the probability that both students would say the same thing? My dad and I think it’s 1 in 16. is that right?
The way that Ronnie wrote his proportion is wrong since 180/x is saying that he will miss 180 days of school. The fraction 1/30 means that he would miss 1 day out of 30 days, which is correct. But the fraction 180/x would mean that he is missing 180 days of school, which is wrong.
The general equation for a straight line is y = mx+c, where m is the gradient/ slope, so m = -5. The first thing we need to do is find c, which we do by plugging in the x and y values that we already know: y = 7 and x = -2
7 = -5*(-2) + c
7 = 10 + c
c = 7-10 = -3
Now, we have the general equation of y = -5x -3 and we can use this to find a.