The answer is <span>180 because </span>12 = 4*3 <span>15 = 3*5 </span> <span>18 = 2*9 </span> <span>20 = 4* 5 </span>
<span>Any common multiple must be a multiple of 4, 9, and 5. Since those three are coprime, the least common multiple is their product: 4*9*5 = 180</span>
