First you have to take 2/5 and make it tenths, those numbers times two are 4/10. That is not enough numbers so you have to take the 1 and make it 10/10, 10/10 plus 4/10 equals 14/10. 14/10-9/10 equals 5/10. you have to find what 8 and 10 can multiply into. That would be 40. 5/8 times 5 equals 25/40 and 5/10 times 4 equals 20/40. 5 25/40-20/40 your final answer is 5 5/40 in lowest terms that is 1/8. Your final answer will be 5 1/8. There is another way i can do it with putting 5/10 in lowest terms and putting it into eights i can do that comment if you want me to do that.