in order to find the reciprocal of 10 1/2 you have to figure out the improper fraction. the improper fraction for that equation would be 21/2. reciprocal means opposite, so when you reciprocal a fraction, you have to put the numerator on the bottom and the denominator on the top. so, 21/2 is 2/21. 2/21 is the reciprocal for 10 1/2 :))
