So, if there are 3 bees and that is equivalent to 15. Then you would divide 15 by 3. (15÷3=5) Each bee=5
Because we know that 3 bees equal 5, we can figure out how much eat dragonfly is worth. If 3 dragonflies + 3 bees (15) = 27 then you would subtract 15 from 27 (27-15=12) So, 3 dragonflies=12
To find out how much each dragonfly is worth you would divide 12÷3=4 because 3 dragonflies=12 then each dragonfly is equal to 4.
Bee=5
Dragonfly=4
You can now solve the remaining two questions using the values above.
Dragonfly(4)+Bee(5)=9
2 Dragonflies=8 because each dragonfly is 4
2 Bees=10 because each bee is 5
2 Dragonflies(8)+2 Bees(10)=18