All categories

2 years ago

Round each number to the nearest ten and estimate the sum.

Mathematics

1 answer:

jeka57 [31]2 years ago

8 0

Answer:

The answer is 470

Step-by-step explanation:

371 round to 370

97 rounds to 100

370+100=470

ANSWER=470

You might be interested in

Please simplify each expression for 18, 20, and 21

NeX [460]

The answer to the questions

5 0

3 years ago

Half an hour after leaving her house Beverly was 20 miles from home. At this point she merged onto the highway and was traveling

N76 [4]

Answer:

1. 45.71 miles

2. 10 miles

3. 89.43 miles

4. 0.79 hr

5. 0.025 hr

Step-by-step explanation:

speed = distance/time

After 4 hrs Beverly was 200 miles from home , however she had spent 0.5hr travelling for 20 miles prior to getting to the highway.

Therefore;

Constant speed before Highway = 20/0.5 = 40 miles/hr

Constant speed at Highway = $\frac{(200-20)}{(4-0.5)}$ = 51.43 miles/hr

1. in 1 hr beverly will have travelled;

⇒ (20 miles in 0.5 hr ) + (0.5 hr at speed 51.43 miles/hr)

⇒ 20 + (0.5 x 51.43) = 45.71 miles

2. In 0.25 hr beverly had not reached the highway

⇒ distance = speed x time

⇒ distance = 40 x 0.25 = 10 miles

3. in 1.85 hrs beverly will have travvelld;

⇒ (20 miles in 0.5 hr ) + (1.35 hr at speed 51.43 miles/hr)

⇒ 20 + 69.43 = 89.43 miles

4. Time taken to get to 35 miles

⇒ (20 miles in 0.5 hr ) + (15 miles at speed 51.43 miles/hr)

⇒ 0.5hr + (15/51.43) hr = 0.79 hr

5. Time taken to travel 1 mile

⇒ time = distance / speed = 1 mile / 40 miles/hr

⇒ time = 0.025 hr

8 0

3 years ago

Starter If x = 3, find y when: a) y = x b) y = 2x c) y = 5x - 2 d) y = x

gogolik [260]

Answer:

a. 3

b. 2(3) is 6

c. 5(3)-2 is 13

d.3

4 0

3 years ago

Read 2 more answers

• A researcher claims that less than 40% of U.S. cell phone owners use their phone for most of their online browsing. In a rando

antiseptic1488 [7]

Answer:

We failed to reject H₀

Z > -1.645

-1.84 > -1.645

We failed to reject H₀

p > α

0.03 > 0.01

We do not have significant evidence at a 1% significance level to claim that less than 40% of U.S. cell phone owners use their phones for most of their online browsing.

Step-by-step explanation:

Set up hypotheses:

Null hypotheses = H₀: p = 0.40

Alternate hypotheses = H₁: p < 0.40

Determine the level of significance and Z-score:

Given level of significance = 1% = 0.01

Since it is a lower tailed test,

Z-score = -2.33 (lower tailed)

Determine type of test:

Since the alternate hypothesis states that less than 40% of U.S. cell phone owners use their phone for most of their online browsing, therefore we will use a lower tailed test.

Select the test statistic:

Since the sample size is quite large (n > 30) therefore, we will use Z-distribution.

Set up decision rule:

Since it is a lower tailed test, using a Z statistic at a significance level of 1%

We Reject H₀ if Z < -1.645

We Reject H₀ if p ≤ α

Compute the test statistic:

$Z = \frac{\hat{p} - p}{ \sqrt{\frac{p(1-p)}{n} }}$

$Z = \frac{0.31 - 0.40}{ \sqrt{\frac{0.40(1-0.40)}{100} }}$

$Z = \frac{- 0.09}{ 0.048989 }$

$Z = - 1.84$

From the z-table, the p-value corresponding to the test statistic -1.84 is

p = 0.03288

Conclusion:

We failed to reject H₀

Z > -1.645

-1.84 > -1.645

We failed to reject H₀

p > α

0.03 > 0.01

We do not have significant evidence at a 1% significance level to claim that less than 40% of U.S. cell phone owners use their phones for most of their online browsing.

8 0

3 years ago

Find area of triangle

ivanzaharov [21]

Answer:

49.1 cm² (round to nearest 10)

Step-by-step explanation:

- use trigonometry to find the height(h) of the triangle

- substitute height and base(b) 12cm into the formula

A = ½ × b × h .

7 0

3 years ago