I am a sequence of numbers where each term after the first two is the sum of the two preceding terms. If my third term is 4 and my fourth term is 7, what is my first term?
1
Let terms be a, b, c (4), d (7). c = a + b = 4. d = b + c = 7 -> b + 4 = 7 -> b = 3. Since a + b = 4 and b = 3, a = 1.
About this riddle
Math riddles hide a calculation inside a short story. Pull out the numbers, work out what is being asked, and watch for a trick such as a unit change.
Difficulty: Medium. More like this: Math riddles with answers or try Target 24 for a different kind of puzzle.
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