Answer:
Ryan use 4. 50 yards of cloth to make 6 backpack.
Step-by-step explanation:
Given : ryan makes 6 backpacks he uses 3/4 of cloth to make each backpack.
To find  : what is the total amount cloth ,in yards ryan use to make all 6 backpacks.
Solution : We have given that 
Ryan make a backpack to use =   of a cloth.
 of a cloth.
Ryan make such 6 backpack = 
                                                 =    .
 .
                                                = 4. 50 yards.
Therefore, Ryan use 4. 50 yards of cloth to make 6 backpack.