Can't figure out how the answer comes out to be true

Question

Can't figure out how come: 0.7 >0.7 is true.Seems to be a trick question.

    void main()
float a=0.7;`

if(a < 0.7)`
{
     printf("TRUE");
}   

    else
    {
         printf("FALSE");
    }
}

Answer 1

This is because variable a is a float, and the constant 0.7 is double. Representation of 0.7 in floating point types is not precise. When the value is converted to float, the result becomes slightly smaller than the double value. This difference could go both ways, i.e. float representation may become slightly greater than the corresponding double after the conversion.

Adding a cast will fix the problem:

if(a < (float)0.7) {
     printf("TRUE");
} else {
     printf("FALSE");
}