The 68-95-99.7 rule tells us 68% of the probability is between -1 standard deviation and +1 standard deviation from the mean. So we expect 75% corresponds to slightly more than 1 standard deviation.
Usually the unit normal tables don't report the area between -σ and σ but instead a cumulative probability, the area between -∞ and σ. 75% corresponds to 37.5% in each half so a cumulative probability of 50%+37.5%=87.5%. We look that up in the normal table and get σ=1.15.
So we expect 75% of normally distributed data to fall within μ-1.15σ and μ+1.15σ
That's 288.6 - 1.15(21.2) to 288.6 + 1.15(21.2)
Answer: 264.22 to 312.98
10(4^2-(9)
Since 16-9 is 7
And 10 times 7 is 70
To solve this problem, we need to get the variable x alone on one side of the equation. To begin, we are going to use the distributive property twice on the left side of the equation to expand the multiplication and get rid of the parentheses.
4(x-1) - 2(3x + 5) = -3x -1
4x - 4 -6x - 10 = -3x - 1
Next, we should combine like terms on the left side of the equation. This means we should add/subtract the variable terms and the constant terms in order to simplify this equation further.
-2x - 14 = -3x - 1
Then, we have to add 3x to both sides of the equation to get the variable terms all on the left side of the equation.
x - 14 = -1
After that, we should add 14 to both sides of the equation to get the variable x alone one the left side of the equation.
x = 13
Therefore, the answer is 13.
Hope this helps!
scientist A dissolved 1 kg of salt in 3 litres.
scientist B dissolved 20 pounds of slat in 7 pint of water.
we know that 1 pound =0.543 g
20 pounds=9.07 kg.
1 pint=0.5 litres
so 7 pints =3.5 litres
so dissoving 1 kg of salt in 3 litres of water and 9.07 kg in 3.5 litres of water
we know that for concentration kg/l units is used .
for A= 1/3=0.33kg/l
and B=9.07/3.5=2.59 kg/l.
so scientist A has prepared more concentrated solution .
Answer:
If It was a Fraction it'd be 8/5
Step-by-step explanation:
