15. Marguerite finds the distance between two boats,
Pand R, on the other side of the river, as follows.
She begins at A, opposite boat P.
From A she walks to B, a distance of 54 m.
She measures the angle ABP as 43° and angle
CBR as 47°.
From these measurements, she is able to find the
distance, PR, between the two boats.
(i) Calculate w, the width of the river, using the
triangle APB.
(ii) Using triangle CBR, calculate the distance |BC|.
Hence find the distance between the boats.
Give each answer in metres, correct to 1 decimal place.