a + b = 645
a - b = 151
Add: 2a = 796
a= 398, making b = 247
645 - 151 = 494 494 / 2 = 247 247 + 151 = 398 Which means: 398 + 247 = 645 and 398 - 247 = 151
398 and 247.
247 + 398 = 645398 - 247 = 151Therefore the two numbers which add together to make 645 and have a difference of 151 are 247 and 398.
Let the two numbers be represented by 'a' and 'b'. Then, a + b = 645 And a - b = 151............adding these two eqations together gives :- 2a = 796 : a = 398..........and b = 645 - 398 = 247 (or b = 398 - 151 = 247).
Guess and check used to be called trial and error. If you look at 645 and realize that 400 and 245 differ by 155, you know you're only four away. So you try 398 and 247 and there you are.
445
Sum means adding so the sum is 645 + 10 = 655. Hope it helped!
The sum of 483 and 162 is 645.
645
The sum of the first 5,000 odd numbers 25,000,000.
1 + 3 + 5 + 15 + 43 + 129 + 215 + 645 = 1,056
The sum is 150*151/2 = 11,325