Date: 04/17/97 at 22:07:29 From: Brian Gage Subject: Stealing eggs There are 10 children going on an Easter egg hunt. Every child finds 10 eggs. Suddenly a mean child steals one egg from each child. How many eggs are left? Alessandra (age 8)
Date: 04/18/97 at 19:13:22 From: Doctor Jodi Subject: Re: Stealing eggs Dear Alessandra, Thanks for your word problem. First of all, if you can, you might want to find some pennies or bingo counters or something like that to help you count all these things. First we have 10 children, with 10 eggs each. How many eggs is that? Let's make a list of the children and how many eggs each has: Child 1: 10 Child 2: 10 Child 3: 10 Child 4: 10 Child 5: 10 Child 6: 10 Child 7: 10 Child 8: 10 Child 9: 10 Child 10: 10 Can you add those all up? (If you do this with piles of pennies or bingo chips, you can make 10 piles of 10 and count them up.) We have a shorthand for adding something to itself a certain number of times. It's called multiplication. Here's 2 X 3, for example: ** ** ** How would you write your addition problem as multiplication? Now that you have the total, we have to see what happens next. Next someone comes along and steals 1 egg from each child. How many eggs is that? Here's another list of the number of eggs stolen from each child: Child 1: 1 Child 2: 1 Child 3: 1 Child 4: 1 Child 5: 1 Child 6: 1 Child 7: 1 Child 8: 1 Child 9: 1 Child 10: 1 We can also write that as 10 x 1. Next we take the first number of eggs (100) and subtract the number of eggs stolen (10). Can you figure out what we get using pennies or counters? There's another way to answer this problem: you can subtract the egg stolen from each child first and then multiply ten times the number of eggs left. What do you think would happen then? Write back if you have more questions or need more help. -Doctor Jodi, The Math Forum Check out our web site! http://mathforum.org/dr.math/
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