"Quick, get the license plate," urged one of the mathematicians, seeing that it was only a 4 digit number. When the car had disappeared around the corner, they put together these characteristics:
1. One of the digits is neither prime nor composite.
2. The digit in the hundreds place is three times the digit in the thousands place.
3. The digit in the ones places is four times the digit in the tens place.
4. The smallest prime number is in the thousands place.
**What number did the four playful mathematicians see on the license plate
School T-shirts ---------- $15.95
School Stickers ---------- $ 1.60
School Baseball Cap-- $12.45
Dad decided to give the money to Mary. "Tell her how much money I should give her so there is no money left over for candy," Dad winked...
All three did quickly looked at the numbers and did some math in their heads. Terry said, "Give her $59." Emily said, "That's not enough so give her $65." Mary said, "It will be less than $64 but that is pretty close."
Without actually adding up all of the pieces, how can you estimate the total to find out approximately how much money will be left over for some candy? Which estimation would you use? Why?
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