 For example, the ratio 4∶5 can be written as 1∶1.25 (dividing both sides by 4) Alternatively, it can be written as 0.8∶1 (dividing both sides by 5).Where the context makes the meaning clear, a ratio in this form is sometimes written without the 1 and the ratio symbol (∶), though, mathematically, this makes it a factor or multiplier.Ratios may also be established between incommensurable quantities (quantities whose ratio, as value of a fraction, amounts to an irrational number).