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							|  |  |  | id: 5900f4231000cf542c50ff34 | 
					
						
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										 |  |  | title: >- | 
					
						
							|  |  |  |   Problem 181: Investigating in how many ways objects of two different colours | 
					
						
							|  |  |  |   can be grouped | 
					
						
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										 |  |  | challengeType: 5 | 
					
						
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											2019-08-05 09:17:33 -07:00
										 |  |  | forumTopicId: 301817 | 
					
						
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											2021-01-13 03:31:00 +01:00
										 |  |  | dashedName: >- | 
					
						
							|  |  |  |   problem-181-investigating-in-how-many-ways-objects-of-two-different-colours-can-be-grouped | 
					
						
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										 |  |  | # --description--
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										 |  |  | Having three black objects B and one white object W they can be grouped in 7 ways like this: | 
					
						
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										 |  |  | (BBBW)(B,BBW)(B,B,BW)(B,B,B,W) | 
					
						
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										 |  |  | (B,BB,W)(BBB,W)(BB,BW) | 
					
						
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										 |  |  | In how many ways can sixty black objects B and forty white objects W be thus grouped? | 
					
						
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										 |  |  | # --hints--
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										 |  |  | `euler181()` should return 83735848679360670. | 
					
						
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										 |  |  | ```js | 
					
						
							|  |  |  | assert.strictEqual(euler181(), 83735848679360670); | 
					
						
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										 |  |  | ``` | 
					
						
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										 |  |  | # --seed--
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										 |  |  | ## --seed-contents--
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							|  |  |  | ```js | 
					
						
							|  |  |  | function euler181() { | 
					
						
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										 |  |  |   return true; | 
					
						
							|  |  |  | } | 
					
						
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							|  |  |  | euler181(); | 
					
						
							|  |  |  | ``` | 
					
						
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										 |  |  | # --solutions--
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							|  |  |  | ```js | 
					
						
							|  |  |  | // solution required | 
					
						
							|  |  |  | ``` |