The unknown number is 48 using the equation: x ÷ 12 +49=53 subtract 49 from both sides and get x ÷ 12 = 4 multiplying by 12 on both side to get rid of the ÷12 and get the final answer of x=48.
The answer is 6 jus do it
Answer:
5 felt pads.
7 cards.
Step-by-step explanation:
Remark
- The total number of items is 12
- So let the felt sheets be x
- Let the cards = y
Equations and Solution
x + y = 12
Now the price is 7.75 that she has to pay for the 12 items. She wants to come back with 0 dollars.
0.5x + 0.75y = 7.75 Multiply this equation by 2
x + 1.5y = 15.50 write the first equation underneath and subtract.
<u>x + y = 12</u>
.5y = 3 Divide by 0.5
y = 3/0.5
y = 7
So she can get 7 cards.
x + y = 12
x + 7 = 12
x = 12 - 7
x = 5
So she can buy 5 felt pads.
Answer: 
Step-by-step explanation:
The first step is to make the division of the fractions
and
. To do this, you can flip the fraction
over and multiply the numerators and the denominators of the fractions. Then:

Reduce the fraction
:

Now you can make the subtraction: in this case the Least Common Denominator (LCD) will be the multiplication of the denominators. Divide each denominator by the LCD and multiply this quotient by the corresponding numerator and then subtract the products. Therefore you get:

Answer:
a) n = 1037.
b) n = 1026.
Step-by-step explanation:
In a sample with a number n of people surveyed with a probability of a success of
, and a confidence level of
, we have the following confidence interval of proportions.

In which
z is the zscore that has a pvalue of 
The margin of error is:

99% confidence level
So
, z is the value of Z that has a pvalue of
, so
.
(a) Assume that nothing is known about the percentage to be estimated.
We need to find n when M = 0.04.
We dont know the percentage to be estimated, so we use
, which is when we are going to need the largest sample size.






Rounding up
n = 1037.
(b) Assume prior studies have shown that about 55% of full-time students earn bachelor's degrees in four years or less.

So






Rounding up
n = 1026.