Rish is sorting bolts for her home repair business. She has an 8-pound bag of bolts. If each kitchen her team repairs requires 1 5 pound of bolts, how many kitchen can she repair? Joshua solves the problem by finding 8 : 1 5 = 40. Melanie solves the problem by finding 8 * 5 = 40

I hope you mean 1/5 when you say 1 5. If that's what you mean, then both, Joshua and Melanie, are correct because, both of their equations are the same.

Joshua's - 8 : 1/5 = 40 (Since we can divide a number by fraction, we use this rule: keep, change flip. When we use that Joshua's equation turns into 8 * 5/1 = 8*5 = 40, same as Melanie's.)