Remember: Please Excuse My Dear Aunt Sally (PEMDAS)
In solving algebraic expressions, there is an order in which to solve it.
<span>1) perform the operation inside the </span>parenthesis<span> first </span>
<span>2) then perform the operation with the </span>exponents
<span>3) apply </span>multiplication<span> and </span>division<span> from left to right of the equation.</span>
<span>4) apply </span>addition<span> and </span>subtraction<span> from left to right of the equation.</span>
Given:
John had to pay a combined electric and gas bill $150.
The electric portion of the bill was $90.
To find:
The ratio of money spent on electric to that on gas.
Solution:
Let x be the amount of gas bill.
The electric portion of the bill was $90 and John had to pay a combined electric and gas bill $150. So,
The gas portion of the bill was $60.
The ratio of money spent on electric to that on gas is:
Therefore, the ratio of money spent on electric to that on gas is 3:2.
Answer:
Yes, both np and n(1-p) are ≥ 10
Mean = 0.12 ; Standard deviation = 0.02004
Yes. There is a less than 5% chance of this happening by random variation. 0.034839
Step-by-step explanation:
Given that :
p = 12% = 0.12 ;
Sample size, n = 263
np = 263 * 0.12 = 31.56
n(1 - p) = 263(1 - 0.12) = 263 * 0.88 = 231.44
According to the central limit theorem, distribution of sample proportion approximately follow normal distribution with mean of p = 0.12 and standard deviation sqrt(p*(1 - p)/n) = sqrt (0.12 *0.88)/n = sqrt(0.0004015) = 0.02004
Z = (x - mean) / standard deviation
x = 22 / 263 = 0.08365
Z = (0.08365 - 0.12) / 0.02004
Z = −1.813872
Z = - 1.814
P(Z < −1.814) = 0.034839 (Z probability calculator)
Yes, it is unusual
0.034 < 0.05 (Hence, There is a less than 5% chance of this happening by random variation.
Answer:
y=10/9x+2
Step-by-step explanation:
slope intercept form is y=mx+b
b is where you begin and mx is your slope
2462.5 half of 4925 50% is 1/2 mean divisions by 2
