| 
							Ryan Martis
							
						 | 
						
							
								  | 
								
									
									 « Reply #1 on: January 18, 2010, 07:11:13 AM »  | 
								
								 | 
							  
							 
							ANSWER : 
  72 Years... 
  Solution: 
  Grandpa: 
  "This problem is conveniently solved by writing down the necessary equations. Note that there are 12 months in a year, 52 weeks in a year, and 365 days in a year. 
  Let m be my age in years. If s is my son's age in years, then my son is 52s weeks old. If g is my grandson's age in years, then my grandson is 365g days old. Thus, 
  365g = 52s. 
  Since my grandson is 12g months old, 
  12g = m. 
  Since my grandson, my son and I together are 120 years, 
  g + s + m = 120. 
  The above system of 3 equations in 3 unknowns (g, s and m) can be solved as follows. 
  m / 12 + 365 m / (52 × 12) + m = 120 or 
  52 m + 365 m + 624 m = 624 × 120 or 
  m = 624 × 120 / 1041 = 72. 
  So, I am 72 years old." 
					 |