An item sold for $ 21.00 more than it cost. If the marked price of this item was 150 \% of its cost price, and if it was sold at a 30 \% discount, then its cost price was?

What is the least common multiple of 16 and 3?

Samantha swam upstream for some distance in one hour. she then swam downstream the same river for the same distance in only 12 minutes. if the river flows at 4 mph, how fast can samantha swim in still water?

What is the lcm of 16 and 40 ? 24 and 40 ?