posted by Shin .
Three ships — the Nina, the Pinta, and the Santa Maria — are setting sail from Spain on a mission to find the shortest route to the West Indies. The year is 1492 and Columbus is about to sail the ocean blue...
"NO! It can't be so!" shouted Captain Devious, commander of the Nina. "I should be the admiral of the Santa Maria. I should be the one to lead us to the West Indies — not some pip-squeak Columbus! Columbus — HA! He probably thinks the earth is round."
The captain's first mate, Sneaky Sam, argued, "He is the greatest admiral of the seven seas, Captain. The Queen Isabella herself has given him gold, supplies, and ships."
"Ah, yes! But he might not be so great if SOMEONE ELSE were to reach the West Indies before him," mused Captain Devious, rubbing his bearded chin. A diabolical plot was hatching in his twisted mind.
"Sneaky, I have an idea: The Santa Maria is scheduled to leave on August 3rd. Let's prepare the Nina for voyage and set sail two days early. If we do, we will be the first to claim the West Indies for Spain. We could become rich and Queen Isabella will make us heroes! What do you say, eh?" cajoled the sly captain with a smile and wink.
"Oh, I get it. You want to CHEAT your way to the West Indies by getting a head start!" cried Sneaky.
"Ssshhh! Do you want everyone to hear you? This is NOT cheating — we are simply making a few departure changes," replied Captain Devious.
Before sunrise the morning of August 1st, Captain Devious and Sneaky Sam set sail on the Nina — two days ahead of schedule. They had 4,300 km to travel from Spain to the San Salvador island of the Bahamas, and were traveling at the pace of 60 km a day.
No one but the twinkling stars knew of their treachery until dawn when Columbus went to the dock and saw the Nina missing. He called the crews of the Santa Maria and the Pinta together.
"Men, we've been betrayed! Devious and his scurvy mate, Sneaky, are trying to rob us of our rightful claim to glory and fame. Are we going to let them get away with this?" cried Columbus.
"NO!" replied the angry crew.
Columbus and his crew worked around the clock to prepare the remaining ships. Bright and early on the summer morning of August 3, 1492, Columbus set sail for the West Indies on his flagship the Santa Maria. With the wind in his face, Columbus pondered: "How fast should we travel to land on San Salvador island five days before Captain Devious?"
Help Christopher Columbus get to the West Indies five days BEFORE the evil Captain Devious and his nasty first mate, Sneaky Sam.
Remember: The total distance from Spain to the San Salvador island of the Bahamas is 4,300 km. Captain Devious and his ship, the Nina, left two days earlier, traveling at a rate of 60 kilometers per day towards San Salvador. Columbus left on the Santa Maria two days later, going to the same destination. How fast must Columbus travel on the Santa Maria to reach San Salvador five days before Captain Devious? Round your answer to the nearest whole number.
--- HOW DO I SOLVE THIS?
We need Columbus to make the trip in 7 days less time, since he left 2 days later. So,
4300/x = 4300/60 - 7
x = 66.5
at 60 km/day, it takes 71.67 days
at 66.5 km/day, it takes 64.67 days, or 7 days less
The real trick is to make the winds blow Columbus faster than they do Capt. Devious.