A bank teller knows that she received 34 dimes and nickels from a customer. If the change totaled $2.05, how many dimes and nickels did she receive?

Respuesta :

d = # of dimes
n= # of nickles

d + n = 34 so d = 34 - n
.10d + .05n = 2.05

substitute d = 34 - n into .10d + .05n = 2.05

.10d + .05n = 2.05
.10( 34 - n) + .05n = 2.05
3.4 - .1n + .05n = 2.05
     -.05n = -1.35
  n = 27

d = 34 - n
d = 34 - 27
d = 7

answer

she received 7 dimes and 27 nickels