+90 Recipical (you have the wrong spelling) is exchanging the numerator and denominator
or simply saying let the number upside down
for example $${\frac{{\mathtt{7}}}{{\mathtt{8}}}}$$ , its recipical is $${\frac{{\mathtt{8}}}{{\mathtt{7}}}}$$
for an integer , for example 5 , its recipical is $${\frac{{\mathtt{1}}}{{\mathtt{5}}}}$$ ( 5=$${\frac{{\mathtt{5}}}{{\mathtt{1}}}}$$)
read more at http://www.mathsisfun.com/reciprocal.html
Relatively prime (you have the wrong spelling again) means the highest common factor/greatest common divisor is always 1
for example , for 2 prime numbers, 3 and 7 , as they have only 1 common factor (here is 1) , they are relatively prime
or 2 connecting number , like 15 and 16 , their common factor is 1 and then they are relatively prime
read more at http://wiki.answers.com/Q/What_is_a_relative_prime_number?#slide=1
