Tina takes Karate classes every Tuesday and Thursday. The classes are 55 minutes long.
Take the 55 minutes and multiply that by 2 {2 represent Tuesday and Thurdsday} 55 x 2 = 110. Tina takes Karate classes for 110 minutes each week. Take the 110 and multiply that by 3 {3 represent the 3 weeks}. 110 x 3 = 330. 330 minutes is 5 hours and 30 minutes.
Tina's total hours of Karate in 3 weeks is 5 hours and 30 minutes.