Find an irrational number betweenness 7.7 and 7.9. explain why it is irrational

Two friends went to get ice cream sundaes. they each chose a flavor of ice cream from a list of vanilla and chocolate and toppings from a list of hot fudge, strawberries, sprinkles, peanuts, and whipped cream. use the sets below describing their choices and find c'. let a = {vanilla, chocolate, hot fudge, strawberries, sprinkles, peanuts, whipped cream} let b = {vanilla, hot fudge, sprinkles, whipped cream} let c = {chocolate, hot fudge, peanuts, whipped cream}