since the ratio is one to 3 there is one trombone for every 3 violas. you can find the answer by doing 9/3=3. so if there are 9 violas there are 3 trombones
If you are adding 2 to each day (which already has 4) in a 2 week period (14 days) than you would have to time 2(14) and 4(14) and add them. Thus would make the answer 84 blocks.
