Mr. Bodhi is transporting some animals using a yacht across a river. He has 20 cows, 15 foxes and three times as many zebras as foxes. To balance the yacht to ensure a smooth sail across the river, the total number of animals in the yacht needs to be 100. If he decides to add sheep to the yacht to make the yacht sail-worthy, how many sheep did he add to the yacht?
The number of cows and foxes in the yacht is 20+15 = <<20+15=35>>35
Mr. Bodhi also has three times as many zebras as foxes in the yacht, equal to 3*15 = <<3*15=45>>45 zebras.
The number of animals in the yacht so far is 35+45 = <<35+45=80>>80
To balance the yacht, Mr. Bodhi needs to add 100-80= <<100-80=20>>20 sheep
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