Let your final bowling score be x. It is 14 pins less than your friends final score. Your friends final bowling score is 105. Then x is 14 pins less than 105.
1 way: This means that 105 is greater than x by 14. Mathematically,
105-x=14,
-x=14-105,
-x=-91,
x=91.
2 way: When you add 14 to x, you'll get 105.
x+14=105,
x=105-14,
x=91.
Answer: Your final score is 91.
