How do you solve this?

This question should be solved by using the binomial coefficient:

Q) Sammy the spider has a rectangular shaped web. He sleeps and eats at (0,0). How many different ways are there to catch a fly that lands at (4,3) if he can only move horizontally and vertically???

#Combinatorics

Easy Math Editor

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Math	Appears as
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`2 \times 3`	$2 \times 3$
`2^{34}`	$2^{34}$
`a_{i-1}`	$a_{i-1}$
`\frac{2}{3}`	$\frac{2}{3}$
`\sqrt{2}`	$\sqrt{2}$
`\sum_{i=1}^3`	$\sum_{i=1}^3$
`\sin \theta`	$\sin \theta$
`\boxed{123}`	$\boxed{123}$

Comments

image

For a grid of $m \times n$ , the number of ways $N = \dbinom {m+n}n$ . In this case it is $N = \dbinom 73 = \boxed{35}$ .

Chew-Seong Cheong - 2 years, 11 months ago

Try this...

Syed Hamza Khalid - 2 years, 11 months ago

Math	Appears as
Remember to wrap math in `\(` ... `\)` or `\[` ... `\]` to ensure proper formatting.
`2 \times 3`	$2 \times 3$
`2^{34}`	$2^{34}$
`a_{i-1}`	$a_{i-1}$
`\frac{2}{3}`	$\frac{2}{3}$
`\sqrt{2}`	$\sqrt{2}$
`\sum_{i=1}^3`	$\sum_{i=1}^3$
`\sin \theta`	$\sin \theta$
`\boxed{123}`	$\boxed{123}$