Question

Put a math symbol between 4 and 5 to get a number bigger than 4 but smaller than 5.

Answer 1

1) decimal point
by putting . between 4 and 5 i.e 4 < 4.5 < 5

2)I'm going to define the symbol⊕
a⊕b = (1/2) (a+b)
so 4⊕5 = (1/2)(4+5)=4.5

Like if satisfied

⊕:R×R→
a⊕b↦


$$$
a$b=12(a+b