English Deutsch Français Italiano Español Português 繁體中文 Bahasa Indonesia Tiếng Việt ภาษาไทย
All categories

Thomas is training his pet frog to climb up a flight of stairs. The frog can hop up only one or two steps, and can not hop down. How many different ways can the frog hop up a flight of 10 stairs? (up 1 up 2 up 1 up 2 up 1 up1 up1 up1 etc.)

WHAT IS THE METHOD OF SOLVING THIS PROBLEM??????

thanks

2007-01-16 07:05:38 · 4 answers · asked by Sean F. 1 in Science & Mathematics Mathematics

4 answers

A good technique is to start with a smaller number of steps and look for a pattern.

For 1 step, there is 1 way: 1
For 2 steps, there are 2 ways: 1,1; 2
For 3 steps, there are 3 ways: 1,1,1; 1,2; 2,1
...
After doing this a few more times, try to make a general formula. Let s(n) = number of ways to go up n steps. Notice that if the first hop is 1 step then there are s(n-1) ways to go up the remaining n-1 steps. Similarly, if the first hop is 2 steps then there are s(n-2) ways to go up the remaining n-2 steps. So we get the recursive formula:

s(n) = s(n-1) + s(n-2)
thus s(n) is the nth fibonacci number (or the n+1st depending upon when you start counting), so s(10) = 89

2007-01-16 07:18:38 · answer #1 · answered by Phineas Bogg 6 · 0 1

it's the exponetial problem, there 2 way frog can leap, either 1 step or 2 step, and there are 10 steps total; therefore,

2^10 ways or 1024 ways

2007-01-16 07:13:25 · answer #2 · answered by Cu Den 2 · 0 1

Hilarious. right it truly is a robust comic tale for you. a woman became out golf faster or later even as she hit the ball into the woods. She went into the woods to seem for it and placed a frog in a capture. The frog stated to her, "in case you launch me from this capture, i visit grant you 3 desires." the female freed the frog, and the frog stated, "thanks,yet I did not indicate that there became a situation on your desires. inspite of you want for, your husband receives cases ten!" the female stated, "it truly is okay." For her first choose, she had to be the most eye-catching lady in the international. The frog warned her, "You do keep in mind that this choose will also make Your husband the most handsome guy in the international, an Adonis whom women folk will flock to. " the female spoke back, "it truly is okay, because i many times is the most eye-catching lady and he will have eyes only for me." So, -she's the most eye-catching lady in the international! For her 2d choose, she had to be the richest lady in the international. The frog stated, "which will make your husband the richest guy in the international and he will be ten cases richer than you." the female stated, "it truly is okay, because what's mine is his and what's his is mine." So, -she's the richest lady in the international! The frog then inquired about her 0.33 choose, and she or he responded, "i'd like a comfortable coronary heart attack." wish you beloved it.

2016-11-24 21:34:36 · answer #3 · answered by Anonymous · 0 0

Hi. Two possibilities for the first step, two for the second, third etc.

2007-01-16 07:11:56 · answer #4 · answered by Cirric 7 · 0 1

fedest.com, questions and answers