Question

The USA is the country with the most personal computers in use, followed by china. If the USA has 115.000 thousand more computers than china and the total number of couputers for both countries is 505,780 thousand, find the number of computers for each country.

Answer 1

2x + 115,000 = 505280
2x = 390,780
x = 195,390

America = x + 115,000 = 310,390
China = x = 195,390

Just to check, 310,390 + 195,390 = 505,780.

Answer 2

Let the number in China be x.

USA has 115 000 more than China  =  x + 115000

Total = 505 780

x + (x + 115000) = 505780

x + x + 115000 = 505780

2x + 115000 = 505780

2x = 505780 - 115000

2x = 390780

x = 390780/2

x = 195 390

So China is x , 195 390,  USA = x + 115000 = 195390 + 115000 = 310390 

China = 195 390

 USA = 310 390

Hope this clarifies it.