Question

在上午10时30分到11点30分之间,时针与分针何时成直角?

Answer 1

(10*5-(60/4))/(1-5/60)

=(50-15))/(1-1/12)

=35/(11/12)

=35*(12/11)

=420/11

=38又(2/11)分

((60/4)-(60-11*5))/(1-5/60)

=(15-(60-55))/(1-1/12)

=(15-5)/(11/12)

=10/(11/12)

=10*(12/11)

=120/11

=10又(10/11)分

在10时38又(2/11)分和11时10又(10/11)分时,时针与分针成直角.