Match each formula to its correct description. 1. simple interest i = prt 2. distance r = d/t 3. time money is invested r = l/pt 4. rate of speed t = i/pt 5. rate of interest t = d/r 6. time spent driving d = rt

Below are the correct matches for each one.

The key is to look at the first letter in the formula. If it involves money and interest, use I = PRT. If it involves distance and times, use d = rt. Each equation is just a manipulation of one of those equations.

1. simple interest                 i = prt 
2. distance                          d = rt  
3. time money is invested   t = i/pt  
4. rate of speed                   r = d/t
5. rate of interest                 r = l/pt  
6. time spent driving            t = d/r