Question

Your piggy bank has a total of 47 coins in it; some are dimes and some are nickels. If you have a total of $3.95, how many nickels do you have?

Answer 1

Help Please.. :)

Answer 2

set up 2 equations in 2 unknowns

the number of dimes and nickels = 47: a + b = 47

some set of "a" dimes and "b" nickels = 3.95: a(.10) + b(.05) = 3.95

Answer 3

systems of equations can be solved by substitution, or elimination

Answer 4

a + b = 47
a(.10) + b(.05) = 3.95


pick your poison :)

Answer 5

since we want to get the number of nickels (b) id opt to get rid of the "a" parts

Answer 6

im confused lol

Answer 7

Given: d = qty of dimes
Given: n = qty of nickels
Given: d + n = total coins =47
Given: total $ = 3.95

Write equations:

d + n = 47
10d + 5n = $3.95

d = 47 - n

substitute:

10(47 - n) + 5n = 395

470 - 10n + 5n = 395

5n = 75

n = 15 ea

d = 47 - 15 = 32 ea

CHECK:

(10)(32) + (5)(15) = 395/100 = $3.95

Answer 8

is this better ?

Answer 9

yes thank you :)

Answer 10

yur welcome =)