200 kg of brass is melted down and cast into ornamental frogs, each weight 3/20kg. How many frogs are made?

1,333 frogs

Step-by-step explanation:

okay so we know that mass remains conserved no matter where you are.

same here ^^

if the total mass of brass is 200 kg

the total mass of the new frogs formed from it when put together will be the same :)

and if there were n such frogs formed

we have,

total mass = n × mass of each frog

200 = n × 3/ 20

n = 4000/ 3

so it becomes something like 1,333.33

that is nearly 1,333 frogs can be made out of 200 kg of brass each weighing 3/ 20kg (the last ones a bit less to make upto 200kg)

{x = -1/2 ,   y = -1

step-by-step explanation:

solve the following system:

{2 x + y = -2

{10 x - 3 y = -2

in the first equation, look to solve for y:

{2 x + y = -2

{10 x - 3 y = -2

subtract 2 x from both sides:

{y = -2 x - 2

{10 x - 3 y = -2

substitute y = -2 x - 2 into the second equation:

{y = -2 x - 2

{10 x - 3 (-2 x - 2) = -2

10 x - 3 (-2 x - 2) = (6 x + 6) + 10 x = 16 x + 6:

{y = -2 x - 2

{16 x + 6 = -2

in the second equation, look to solve for x:

{y = -2 x - 2

{16 x + 6 = -2

subtract 6 from both sides:

{y = -2 x - 2

{16 x = -8

divide both sides by 16:

{y = -2 x - 2

{x = -1/2

substitute x = -1/2 into the first equation:

{y = -1

{x = -1/2

collect results in alphabetical order:

answer:   {x = -1/2 ,   y = -1

b). 4320 have a nice day