Answer:
105 boats
Step-by-step explanation:
Let x be the total number of boats in the marina.
If Two-thirds of the boats in the marina are white.
Fraction of the remaining boat= 1-⅔ =⅓
4/7 of the remaining boats are blue.
4/7 of ⅓ are blue
4/7 X ⅓ = 4/21 are blue
Fraction of Red Boats =
1-(Proportion of white Boats +Proportion of Blue Boats)
= 1-(2/3+4/21)=1/7
If there are 15 red boats,
1/7 of the total boats =15
1/7 X x=15
x=15X7
x=105
There are 105 boats in total on the marina