1. The answer would be (D). This is because you will plug is the (x) of the ordered pair into the equation(y=-2x), so first off would be (y=-2(-2)). since your multiplying a negative time a negative, you will get your (y) which is 4. Now you do this with the rest. -2(1)=-2 and -2(3)=-6. 2. This would be (A). This answer is simple. First you will take one of the equations (y=-x-1) and plug x into it's place so, y=-3-1, getting your answer(y) as being -4. Now you do the same with the other pair. y=-5-1, getting -6, showing (A) as your answer. 3.The answer will be (A)y is 2 times x. this is because you wou would make out the equation from the answer (y=2x). Now knowing your equation, all thats left is plugging in your (x) factors. so y=2(1), getting your (y) value of 2 and you would do this with the rest of your x factors. 4. y=5+x y=5+(2)= 7 y=5+(3)= 8 y=5+(4)= 9 5. (B)y is 3 times x y=3(x) y=3(3)=9 y=3(4)=12 y=3(5)=15 6. (C)y is 6 less than x y=6-(x) y=6-(8)=2 y=6-(9)=3 y=6-(10)=4
A normal curve has approximately 95% of graph between mean - 2sd and mean + 2sd So 95% of the times will be between 0 and 12 minutes. 6 - 2x3 to 6 + 2x3 2.5% will take over 12 minutes
Strangely 2.5% will also take less than 0 minutes to process which shows the normal curve is not perfect in this example.