MATHEMATICS
MIDDLE SCHOOL

Answer: Divide 2520 into 18 or set up a proportion 2520/18= x/1

MIDDLE SCHOOL

A metalworker has a metal alloy that is 25% copper and another alloy that is 60% copper.How many kilograms of each alloy should the metalworker combine to create 50kg of a 46% copper alloy

Answer:

20kg of 25% copper alloy

30kg of 60% copper alloy

Step-by-step explanation:

There are 2 kinds of metal, first metal(A) have 25% copper while the second metal(B) has 60% copper. The metalworker want to create 50kg of metal, which means the total weight of both metals is 50kg (A+B = 50). The metalworker also want the metal made of a 46% which is 23kg(0.25A + 0.6B = 0.46*50). From these sentences, we can derive 2 equations. We can solve this with substitution.

A+B = 50

A= 50-B

Let's put the first equation into the second.

0.25A + 0.6B = 0.46 *50

0.25(50-B) + 0.6B =23

12.5 - 0.25B + 0.6B =23

0.35B=23 -12.5

B= 10.5/ 0.35= 30

Then we can solve A

A= 50-B

A= 50-30

A=20

MIDDLE SCHOOL

What is the best approximation for the area of this circle? the diameter is 6 Use 3.14 to approximate pi. please help

Area=.25*pi*d^2

A=.25*(3.14)*(36)

A=28.26

A=.25*(3.14)*(36)

A=28.26

MIDDLE SCHOOL

Julia finds that the data in the table can be modeled by the function y = 5(4)x. A 2-column table with 5 rows. The first column is labeled time (minutes) with entries 0, 1, 2, 4, 8. The second column is labeled distance (feet) with entries 5, 20, 80, 320, 640.

Which statement about Julia’s finding is true?

Julia is correct because the distance starts at 5 feet and increases by a factor of 4.

Julia is correct because the function is true for (0, 5) and (1, 20).

Julia is not correct because the function is not true for the point (2, 80).

Julia is not correct because the distance does not increase by a constant factor each minute.

Answer:

Julia is not correct because the distance does not increase by a constant factor each minute.

Step-by-step explanation:

Julia modeled the data in the table by the function .

A 2-column table with 5 rows. The first column is labeled time (minutes) with entries 0, 1, 2, 4, 8. The second column is labeled distance (feet) with entries 5, 20, 80, 320, 640.

The values of y corresponding to the values of x are correct up to x = 2.

Now, for x = 4, the value of y is 1280 ≠ 320 and for x = 8, the value of y will be 327680 ≠ 640

Therefore, Julia is not correct because the distance does not increase by a constant factor each minute. (Answer)

Answer:

D

Step-by-step explanation:

just took test

HIGH SCHOOL

14b=-56 what is the answer

Divide 14 by iits opposite (-14) to cancel and divide on the other sid eof equal street to get the answer positive 4