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When, Oh, When?
Question：Ken promised Ben today to tell him a big secret on the day before five days from the day after tomorrow. Today is Saturday, October 21. On what day and date will Ken tell Ben the secret?
Answer：
Ken will tell Ben the secret on Friday, October 27.
Two Moves
Question：
Can you change two rows of Xs into a circle by moving only two of the Xs?
Go from this:
X X X
X X X
to this:
X X
X X
XX
by moving only two Xs.
Hint：Try it by using pennies. But remember, you can move only two of the pennies. The others stay exactly where they are!
Answer：
Move the X at the right in the top row and the X in the middle of the bottom row to the position of the bottom two Xs in the circle.
编辑/孙栎栎
Question：Ken promised Ben today to tell him a big secret on the day before five days from the day after tomorrow. Today is Saturday, October 21. On what day and date will Ken tell Ben the secret?
Answer：
Ken will tell Ben the secret on Friday, October 27.
Two Moves
Question：
Can you change two rows of Xs into a circle by moving only two of the Xs?
Go from this:
X X X
X X X
to this:
X X
X X
XX
by moving only two Xs.
Hint：Try it by using pennies. But remember, you can move only two of the pennies. The others stay exactly where they are!
Answer：
Move the X at the right in the top row and the X in the middle of the bottom row to the position of the bottom two Xs in the circle.
编辑/孙栎栎