Yumi wants to hire a dragon to protect her village. She earns 48 coins each day. A dragon costs 1,680) coins. Find how many days it takes Yumi to earn enough coins for a dragon. Which equations represent the problem?
a. 1.680 x ? = 48
b. 48 ÷ ? = 1680
c. ? x 48 = 1680
d. 48 ÷ 1680 = ?
e. 48 x 1680 = ?
f. 1680 ÷ 48
