All categories

3 years ago

A two-digit number is such that the sum of its digits is 12 and the ones digit is twice its tens digit. Find the number.

Mathematics

1 answer:

STatiana [176]3 years ago

4 0

8 plus 4 is 12 and 8 would be twice as much as 4 which is the tens place

You might be interested in

Boxes of raisins are labeled as containing 22 ounces. Following are the weights, in the ounces, of a sample of 12 boxes. It is r

ZanzabumX [31]

Answer:

A 90% confidence interval for the mean weight is [21.78 ounces, 21.98 ounces].

Step-by-step explanation:

We are given the weights, in the ounces, of a sample of 12 boxes below;

Weights (X): 21.88, 21.76, 22.14, 21.63, 21.81, 22.12, 21.97, 21.57, 21.75, 21.96, 22.20, 21.80.

Firstly, the pivotal quantity for finding the confidence interval for the population mean is given by;

P.Q. = $\frac{\bar X-\mu}{\frac{s}{\sqrt{n} } }$ ~ $t_n_-_1$

where, $\bar X$ = sample mean weight = $\frac{\sum X}{n}$ = 21.88 ounces

s = sample standard deviation = $\sqrt{\frac{\sum (X-\bar X)^{2} }{n-1} }$ = 0.201 ounces

n = sample of boxes = 12

$\mu$ = population mean weight

Here for constructing a 90% confidence interval we have used a One-sample t-test statistics because we don't know about population standard deviation.

So, 90% confidence interval for the population mean, $\mu$ is ;

P(-1.796 < $t_1_1$ < 1.796) = 0.90 {As the critical value of t at 11 degrees of

freedom are -1.796 & 1.796 with P = 5%}

P(-1.796 < $\frac{\bar X-\mu}{\frac{s}{\sqrt{n} } }$ < 1.796) = 0.90

P( $-1.796 \times {\frac{s}{\sqrt{n} } }$ < ${\bar X-\mu}$ < $1.796 \times {\frac{s}{\sqrt{n} } }$ ) = 0.90

P( $\bar X-1.796 \times {\frac{s}{\sqrt{n} } }$ < $\mu$ < $\bar X+1.796 \times {\frac{s}{\sqrt{n} } }$ ) = 0.90

90% confidence interval for $\mu$ = [ $\bar X-1.796 \times {\frac{s}{\sqrt{n} } }$ , $\bar X+1.796 \times {\frac{s}{\sqrt{n} } }$ ]

= [ $21.88-1.796 \times {\frac{0.201}{\sqrt{12} } }$ , $21.88+1.796 \times {\frac{0.201}{\sqrt{12} } }$ ]

= [21.78, 21.98]

Therefore, a 90% confidence interval for the mean weight is [21.78 ounces, 21.98 ounces].

8 0

3 years ago

[5x+10y+15z=60 [2x+4y+6z=60 [x+2y+3z=60

Alla [95]

9514 1404 393

Answer:

no solution

Step-by-step explanation:

The equations are inconsistent. The set of equations reduces to ...

x + 2y + 3z = 12

x + 2y + 3z = 30

x + 2y + 3z = 60

No values of x, y, and z can satisfy all three equations. There is no solution.

4 0

2 years ago

Determine the volume of a rectangle box with a link of 5 inches height of 7 inches and the width of 9 inches

taurus [48]

The answer is 315. just multiply all of the numbers.

8 0

3 years ago

you buy 75 candy bars at a cost of $0.49 each what is the total cost of 75 candy bars? use mental math

avanturin [10]

It took me a second but its $36.75

7 0

3 years ago

Read 2 more answers

Howdoyouwrite 1/2 as a percentage?

Orlov [11]

Answer:

50 %

Step-by-step explanation:

1/2 is 0.5 in decimal is 50 %

4 0

1 year ago

Read 2 more answers