Pretty sure you have to use 割 but I don't know which pronunciation to use and how to say "equals" in this context.
It's read as 「24割る8は4」「にじゅうよんわるはちはよん」[nijuu yon waru hachi wa yon]. (I think we often say「24割る8イコール4」「にじゅうよんわるはちイコールよん」[nijuu yon waru hachi ikooru yon] after junior high school...) Wait, 24÷8=...4? Isn't it 3?
As Chocolate answered correctly, "equal" is usually omitted, but if you want to say it, it would be である, or なり (natural in this context but archaic). The one with イコール that Chocolate mentions is often heard, but I do not think it is a grammatical Japanese sentence. It is tracing the mathematical notation token by token.