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3 years ago

What is 13.5+5.7+36.5 using mental math

Mathematics

2 answers:

arlik [135]3 years ago

7 0

Answer: 55.7

Step-by-step explanation:

.5 + .5 = 1

1 + 13 = 14

6 + 4 = 10

10 + 10 = 20

20 + 30 = 50

50 + 5.7 = 55.7

tekilochka [14]3 years ago

5 0

55.7

you can add 13.5 and 36.5 in your head that will get rid of the decimal so you get 50. then add 5.7 which is 55.7

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A small box of oranges costs $9 and weighs 12 pounds. A large box of oranges costs $18 and weighs 30 pounds. Right now one of th

jeka94

Answer:

See Below

Step-by-step explanation:

Small Box:

9 dollars for 12 pounds

Per pound cost is:

9/12 = $0.75 per pound

Large Box:

18 dollars for 30 pounds

Per pound cost is:

18/30 = $0.60 per pound

Better deal is large box.

To make the deals same, we can change the number of pounds in the large box. We can lessen it so it becomes the same ratio as dollars to pound.

Small box was

9 to 12

Large box is 18 dollars to WHAT?

18 is double of 9 so, "WHAT" should be double of 12, which is:

12 * 2 = 24

So, we can change large box "30" pounds to "24" pounds.

So, the ratio becomes (cost per pound):

18/24 = $0.75 per pound (same)

4 0

3 years ago

Which equation represents a circle whose center is located at (- 6, 2) and whose radius is sqrt(10) units?

azamat

Answer:

${(x + 6)}^{2} + {(y - 2)}^{2}=10$

Step-by-step explanation:

The equation of a circle with center (a,b) and radius r, is

${(x - a)}^{2} + {(y - b)}^{2} = {r}^{2}$

From the question, the center of the circle is located at (-6,2) and the radius is

$r = \sqrt{10}$

We substitute the center and radius to get:

${(x - - 6)}^{2} + {(y - 2)}^{2} = {( \sqrt{10} })^{2}$

Simplify to obtain:

${(x + 6)}^{2} + {(y - 2)}^{2}=10$

7 0

3 years ago

Round each number to the nearest ten thousand and then subtracting

katrin [286]

Answer:

43,000

Step-by-step explanation:

7 0

3 years ago

The probability that a lab specimen contains high levels of contamination is 0.10. A group of 4 independent samples are checked.

galben [10]

Answer:

a) 0.6561

b) 0.2916

c) 0.3439

Step-by-step explanation:

We are given the following information:

Let us treat high level of contamination as our success.

p = P(High level of contamination) = P(success) = 0.10

n = 4

The, by binomial distribution:

$P(X=x) = \binom{n}{x}.p^x.(1-p)^{n-x}\\\text{where x is the number of success}$

a) P(No high level of contamination)

We put x = 0, in the formula.

$P(X=0) = \binom{4}{0}.(0.10)^0.(1-0.10)^{4} =0.6561$

Probability that no lab specimen contain high level of contamination is 0.6561

b) P(Exactly one high level of contamination)

We put x = 1, in the formula.

$P(X=1) = \binom{4}{1}.(0.10)^1.(1-0.10)^{3} =0.2916$

Probability that no lab specimen contain high level of contamination is 0.6561

c) P(At least one contains high level of contamination)

$p(x \geq 1) = 1 - p( x = 0) = 1 - 0.6561 = 0.3439$

Probability that at least 1 lab specimen contain high level of contamination is 0.3439

8 0

3 years ago

Please help! Im so dumb (　-̥̥̥̥̥̥̥̥̥̥̥̥̥̥̥̥̥̥̥̥̥̥̥̥̥᷄ ω-̥̥̥̥̥̥̥̥̥̥̥̥̥̥̥̥̥̥̥̥̥̥̥̥̥᷅ )

klio [65]

ANSWER:

For the first picture, it is the first answer. This is because of the Exterior Angle Theorem.

For the second picture, use the Exterior Angle Theorem again, but this time, solve for x.

$132 = x + (3x-24)\\132 = 4x - 24\\156=4x\\x=39$

The m∡B = 39°

3 0

3 years ago

What is 13.5+5.7+36.5 using mental math​

What is 13.5+5.7+36.5 using mental math