how many times are the hands of a clock at right angle in 6 hours ?
"in 12 hours , they are at right angles 22 times . in 6 hours , they are at right angles 11 times . answer : option c"
divide(multiply(multiply(multiply(const_12, const_2), 6), subtract(multiply(const_12, const_4), const_4)), multiply(const_12, const_2))