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put this solution on YOUR website!If we mark number of bicycles as b and number of tricycles as t then we have the following:
b is by 1 less than 4 times t ->
Knowing that bicycle has 2 wheels and tricycle has 3 we have:
total number of wheels is 174 ->
Substitute b in the second equation with the first:

, multiply

, combine

, add 2 to the both sides of equation

, divide both sides by 11

, this is the number of tricycles

, substitute t with 16

, this is the number of bicycles
check:
2b+3t=2*63+3*16=126+48=174, OK