Question

what do I do after this step? there are 24 coins, some nickels and some quarters, which add up to $3.40. ok, so ik to do n+q=24 and .05n+.25q=3.4, but idk what to do next

Answer 1

solve the 2 eqns
n+q=24------eqn(1)
.05n+.25q=3.4 -----eqn(2)
multiply above eqn with 100
5n+25q=340 -------eqn(III)

we need to solve eqn (I) and(III)

multiply eqn (I) with 5
n+q=24
5n+5q=120----eqn(IV)

Answer 2

solve eqn (III) and (IV)

subtract eqn(IV) from eqn(III)
5n+25q=340
-(5n+5q=120)
--------------
20q=220

q=11

put value of q in any of given eqn

n+q=24
n+11=24
n=13

so n=13 and q=11