Nice use of brackets. We know exactly what you mean.
(10 - 7 + 2) / (-2 + 1) Notice that with an even number of - signs, you get a plus and with and odd number you get a minus.
(5) / (-1) = - 5 answer
Edit
Numerator
10 does not change.
+ - 7 Here a plus and a minus are put together. There is 1 minus sign which is an odd number of minus signs so the 7 is minus
- - 2 Here there are 2 minus signs. They become plus because 2 is even, and an even number of minuses become a plus so you have +2
10 - 7 + 2 = 5
Denominator
-2 does not change. It remains minus 2.
- - 1 There are 2 minus signs so this becomes plus 1.
- 2 + 1 = - 1
Numerator over denominator = 5/-1 = - 5. I'll probably run out of editing time. If you still don't understand, try and pinpoint the problem and we'll keep trying until you do see it. This question is worth it.
The answer would be 3:33333
The correct answer is a
(X+1)^2 - x^2=23
X^2 + 2x + 1 -x^2 =23
2x +1 =23
2x =22
X= 11
X+1= 12
The answer is D.
If it rotates around the origin for 2 quadrants then it would have rotated 180 degrees.
Answer: the incubation time that separates the bottom 2.5% from the rest of the incubation times is 24.96 days.
Step-by-step explanation:
Suppose the incubation times are approximately normally distributed, we would apply the formula for normal distribution which is expressed as
z = (x - µ)/σ
Where
x = incubation times.
µ = mean time
σ = standard deviation
From the information given,
µ = 23 days
σ = 1 day
The probability value for the incubation time that separates the bottom 2.5% from the rest of the incubation times would be (1 - 2.5/100) = (1 - 0.025) = 0.975
Looking at the normal distribution table, the z score corresponding to the probability value is 1.96
Therefore,
1.96 = (x - 23)/1
x = 1.96 + 23
x = 24.96