Answer:
• Two $10 bills
• Four $20 bills
Step-by-step explanation:
We are told that Gerardo received a number of $20 and $10 bills upon changing a $100 bill at the bank. We are also told that he received 2 more $20 bills than $10. Then we are asked to find the number of each kind of bill.
To solve this problem, let's consider the number of $10 bills he received was [tex]x[/tex]. Since he received 2 more $20 bills, he got [tex](2 + x)[/tex] $20 bills. Therefore, in total he received:
[tex]10 \times x + 20 \times (x +2)[/tex]
This should add up to $100 since that is the amount he changed. Solving the resulting equation for [tex]x[/tex] will give us the number of $10 bills he received.
[tex]10 \times x + 20 \times (x +2) = 100[/tex]
⇒ [tex]10x + 20x + 40 = 100[/tex]
⇒ [tex]30x +40 = 100[/tex]
⇒ [tex]30x + 40 - 40 = 100 - 40[/tex] [Subtracting 40 from both sides of equation]
⇒ [tex]30x = 60[/tex]
⇒ [tex]\frac{30}{30}x = \frac{60}{30}[/tex] [Dividing both sides of the equation by 30]
⇒ [tex]x = \bf 2[/tex]
Therefore, he received 2 $10 bills.
Since the number of $20 bills is 2 more than the number of $10 bills,
no. of $20 bills = 2 + 2
= 4
