The aquarium has 198 guppies, angelfish and catfish altogether. There are 4 times as many guppies as angelfish. There are 6 more
angelfish than catfish.
How many catfish are there?

Number of catfish = 28

Step-by-step explanation:

Let the number of catfish = c

Number of angle fish = c + 6

Number of guppies = 4*(c + 6) = 4c + 4*6 = 4c + 24

Total fishes = 198

c + c + 6 + 4c + 24 = 198           {Combine like terms}

c + c +4c + 6 + 24 = 198

                6c + 30 = 198              {Subtract 30 from both sides}

                     6c    = 198 - 30

                     6c   = 168

                       c = 168/6           {Divide both sides by 6}

                       c = 28

d

step-by-step explanation:

1. d.90

2. e. none of these (80)

3. a. 0

4. b. 6

5. e. none of these (10)

6. a. 5