Mr. Tan puts up poles from one end of a road to the other at equal distances apart. There are 27 wooden poles. The width of each pole is 10 cm. The distance between 2 poles is 30 m. Find the length of the road.
Xuxian and Rachel had the same number of marbles. After Rachel gave away 10 marbles and Xuxian gave away 22 marbles, Rachel had 3 times as many marbles as Xuxian. How many marbles did each of them have at first?
Krishnan had 64 coins in his coin ox. There were 20-cent coins and 50-cent coins. The total value of all the coins was $ 18.50. How many 20-cent coins and 50-cent coins were there?