Respuesta :

Answer:

$10 bill = 14 and  $20 bill = 16.

Step-by-step explanation:

Given  : A cashier has 30 bills, all of which are $10 or $20 bills. The total value of the money is $460.

To find :  How many of each type of bill does the cashier have.

Solution : We have given that

A cashier has 30 bills

Let bill of $10  = x .

Bill of $20 = y .

Money of  $10  = 10x .

Money of  $20  = 20y.

Total bill

x + y = 30-------(1)

10x + 20y = 460-----(2)

On multiplying equation 1 by 10 and subtracting from equation 2.

10x + 20 y = 460

(-)10x +(-) 10 y =  (-)300

______________

0  +  10 y = 160 .

On dividing  by 10

y  = 16 .

Plug y = 16 in equation 1

x + 16  = 30

On subtracting both sides by 16.

x = 30 - 16.

x  = 14

Therefore, $10 bill = 14 and  $20 bill = 16.