Two numbers differ by 9. the large number is 20 greater than half of the smaller number. find the two numbers

Large = 20+ 1/2 of small and,

Large-small =9 so if we put back the 9 to the small one will get the large number
Large=9+small

Now we can see that
20+small/2 =9+ small
20-9=small-small/2
11=half of small so small is 22

Large = 20 + 11=31

Multiply 9 and 67. then multiply 3 with 67. lastly the answer that you got for 9x67 is to be subtracted by the answer you got for 3x67