Respuesta :

Answer:

100th customer is the first desired customer who received both the gift cards.

Step-by-step explanation:

$5 gift card is received by every 20th Customer.

⇒ The customers who receive this $5  card are:

20th Customer, 40th Customer , 60th Customer , 80th Customer, 100th Customer, 120th Customer .... and so on

Also, $10 gift card is received by every 50th Customer.

⇒ The customers who receive this $10  gift are:

50th Customer, 100th Customer , 150th Customer , 200th Customer ......

Among all the customers the 100th customer is the first customer who receives $5 gift card as well as the $10 gift card.

Hence, 100th customer is the first desired customer who received both the gift cards.