write as a fraction or a mixed number in simplest form 1.4%=

Since Percent means "Per 100", then 1.4% = 1.4 per 100 = 1.4/100 (and multiplying by 10/10 to get rid of the decimal in the numerator) = 14/1000 as a fraction.

HOWEVER- both 14 and 1000 are divisible by 2, so 14/1000 = 7/500 .