The hands of a clock suggest an angle whose measure is continually changing. How many degrees does a minute hand move through during a 21-minute time interval?

Question

_{The hands of a clock suggest an angle whose measure is continually changing. How many degrees does a minute hand move through during a 21-minute time interval?} 

Answer 1

Hi Vanessa-

 

The face of a clock is a circle, and a full circle contains 360 degrees.  A full hour contains 60 minutes.  

 

All you have to do a set up a ratio:  21/60 minutes is the same as x/360 degrees.  Perform the operation, and you discover that after 21 minutes have passed, the minute hand will have moved 126 degrees.

Answer 2

This is a ratio problem

 

The hand moves 21 minutes out of 60 possible in the full circle.

A full circle has 360 degrees.

 

SO set up a ratio using the syntax you are being taught

21:60::X:360   or 21/60 = x/360

 

Then solve for X  by

inner product = outer product  ie  60 x X = 21 x 360

or cross multiplication  ie   21 x 360 = X x 60

Answer 3

This answer has been deleted since it was wrong and I did not want to mislead any students who may use it. Thanks to those who answered the question correctly.