31a) Think of $30.90 as 100% of her bill, we first want to find 6%
To work out how much this is, we need to divide the percentage by 100 to get a multiplier (decimal)
6/100 = 0.06
Multiply 0.06 and $30.90 to get the tax
$30.90 x 0.06 = 1.854
As we can't have part of a cent, we round to the nearest 100th
If the number to the right of this value is below 5 we round down, 5 or more we round up
4 is below 5 so we round down
$1.85
31b) For the total bill, we need to add together the original and the tax
$30.90 + $1.85 = $32.75
32a) Simple Interest = PRT
This means
P x R x T
We need to multiply together the Principal, Rate and Time span
We need to turn the percentage into a decimal, so we divide by 100 like before
3.2 / 100 = 0.032
$750 x 0.032 x 6 = $144
32b) To find the account balance, we need to add the interest to the original amount
$750 + $144 = $894
7x - 44 = 4x + 4
Add both sides 44
7x - 44 + 44 = 4x + 4 + 44
7x = 4x + 48
Subtract both sides 4x
7x - 4x = 4x - 4x + 48
3x = 48
Divide both sides by 3
3x ÷ 3 = 48 ÷ 3
<h2>x = 16 </h2>
______________________________
Suppose that the angle between 39 and 4x + 4 is t degrees as you know they make a straight line together thus :
39 + t + 4x + 4 = 180
39 + t + 4(16) + 4 = 180
39 + t + 64 + 4 = 180
39 + t + 68 = 180
t + 107 = 180
Subtract both sides 107
t + 107 - 107 = 180 - 107
<h2>t = 73 </h2>
_____________________________
8y - 43 = 4x + 4 + t
8y - 43 = 4(16) + 4 + 73
8y - 43 = 64 + 4 + 73
8y - 43 = 68 + 73
8y - 43 = 141
Add both sides 43
8y - 43 + 43 = 141 + 43
8y = 184
Divide both sides by 8
8y ÷ 8 = 184 ÷ 8
<h2>y = 23 </h2>
Answer:
The significance level is
and since we are conducting a right tailed test we need to find a critical value who accumulate 0.01 of the area in the right of the normal standard distribution and we got:

So we reject the null hypothesis is 
Step-by-step explanation:
For this case we define the random variable X as the number of entry-level swimmers and we are interested about the true population mean for this variable . On specific we want to test this:
Null hypothesis: 
Alternative hypothesis: 
And the statistic is given by:

The significance level is
and since we are conducting a right tailed test we need to find a critical value who accumulate 0.01 of the area in the right of the normal standard distribution and we got:

So we reject the null hypothesis is 
20
This is because
2x+(6x+20)=180
8x+20=180
8x=160
8x/8=160/8
X=20