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4 years ago

Which of the following is the square of an even number? a.625 b.169 c.441 d.100

Mathematics

1 answer:

professor190 [17]4 years ago

3 0

Answer
D.) 100
Step by step explanation

10^2 = 100

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How would u do this problem ?? #9

Ad libitum [116K]

Since the scale factor is 4:3 then every dimension of triangle WXY is (3/4) of every dimension of triangle CDE.
The perimeter of triangle CDE = 13 + 22 + 29 = 64.
So, the perimeter of triangle WXY = (3/4) * 64 = 48

5 0

3 years ago

Outside a home, there is a 7-key keypad numbered 1 through 7. The correct five-digit code will open the garage door. The numb

julia-pushkina [17]

Answer:

a: 16807

b: 0.0000595

Step-by-step explanation:

(a): We have 7 possibilities of numbers, and we need to choose 5 numbers that can repeat. So, for each of the 5 numbers, we have 7 possibilities. To determine how many codes are possible, we just need to multiply the number of possibilities of each of the 5 numbers, so we have 7x7x7x7x7, or 7^5, which is 16807 possibilities.

(b): to put the correct code in the first try, we need to find the exact combination (just one combination) among these 16807 possibilities, so the probability is 1/16807, which is 0.0000595, or 0.00595%.

8 0

3 years ago

Read 2 more answers

In a regression analysis involving 30 observations, the following estimated regressionequation was obtained.y^ =17.6+3.8x 1 −2.3

USPshnik [31]

Answer:

(a) There is a significant relationship between y and $x_1, x_2, x_3, x_4$

(b) $SSE_{(x_1 ,x_2 ,x_3 ,x_4) }= 45$

(d) $x_1$ and $x_4$ are significant

Step-by-step explanation:

Given

$y = 17.6+3.8x_1 - 2.3x_2 +7.6x_3 +2.7x_4$ --- estimated regression equation

$n = 30$

$p = 4$ --- independent variables i.e. x1 to x4

$SSR = 1760$

$SST = 1805$

$\alpha = 0.05$

Solving (a): Test of significance

We have:

$H_o :$ There is no significant relationship between y and $x_1, x_2, x_3, x_4$

$H_a :$ There is a significant relationship between y and $x_1, x_2, x_3, x_4$

First, we calculate the t-score using:

$t = \frac{SSR}{p} \div \frac{SST - SSR}{n - p - 1}$

$t = \frac{1760}{4} \div \frac{1805- 1760}{30 - 4 - 1}$

$t = 440 \div \frac{45}{25}$

$t = 440 \div 1.8$

$t = 244.44$

Next, we calculate the p value from the t score

Where:

$df = n - p - 1$

$df = 30 -4 - 1=25$

The p value when $t = 244.44$ and $df = 25$ is:

$p =0$

So:

$p < \alpha$ i.e. $0 < 0.05$

Solving (b): $SSE(x_1 ,x_2 ,x_3 ,x_4)$

To calculate SSE, we use:

$SSE = SST - SSR$

Given that:

$SSR = 1760$ ----------- $(x_1 ,x_2 ,x_3 ,x_4)$

$SST = 1805$

So:

$SSE_{(x_1 ,x_2 ,x_3 ,x_4)} = 1805 - 1760$

$SSE_{(x_1 ,x_2 ,x_3 ,x_4) }= 45$

Solving (c): $SSE(x_2 ,x_3)$

To calculate SSE, we use:

$SSE = SST - SSR$

Given that:

$SSR = 1705$ ----------- $(x_2 ,x_3)$

$SST = 1805$

So:

$SSE_{(x_2,x_3)} = 1805 - 1705$

$SSE_{(x_2,x_3)} = 100$

Solving (d): F test of significance

The null and alternate hypothesis are:

We have:

$H_o :$ $x_1$ and $x_4$ are not significant

$H_a :$ $x_1$ and $x_4$ are significant

For this model:

$y =11.1 -3.6x_2+8.1x_3$

$SSE_{(x_2,x_3)} = 100$

$SST = 1805$

$SSR_{(x_2 ,x_3)} = 1705$

$SSE_{(x_1 ,x_2 ,x_3 ,x_4) }= 45$

$p_{(x_2,x_3)} = 2$

$\alpha = 0.05$

Calculate the t-score

$t = \frac{SSE_{(x_2,x_3)}-SSE_{(x_1,x_2,x_3,x_4)}}{p_{(x_2,x_3)}} \div \frac{SSE_{(x_1,x_2,x_3,x_4)}}{n - p - 1}$

$t = \frac{100-45}{2} \div \frac{45}{30 - 4 - 1}$

$t = \frac{55}{2} \div \frac{45}{25}$

$t = 27.5 \div 1.8$

$t = 15.28$

Next, we calculate the p value from the t score

Where:

$df = n - p - 1$

$df = 30 -4 - 1=25$

The p value when $t = 15.28$ and $df = 25$ is:

$p =0$

So:

$p < \alpha$ i.e. $0 < 0.05$

Hence, we reject the null hypothesis

7 0

3 years ago

A rectangle measures 2 1/2 meters by 1 3/4 meters. What is its area?

REY [17]

Answer:

4 3/8

Step-by-step explanation:

1. We can use the formula

Area = L (length) x W (width)

2. The area is unknown so we can substitute it for a

The length and width are both known, so we can plug them in.

a= 2 1/2 x 1 3/4

3. Solve by multiplying

a=4 3/8

3 0

3 years ago

Simply the square root of 240

Novay_Z [31]

15.5 (Just round 15.49 to the nearest tenth)

8 0

3 years ago

Read 2 more answers