Question 90774

    if a stick that is 13 inches long casts a shadow of length 16 inches at the same time an office buildings shadow is 85 ft. long, how tall is the building? Round to one decimal place

    Length of the stick  is  = 13 inch  = 13/12ft

    shadow of the stick   is  = 16 inch  = 16/12  ft

    shadow of the building is = 85 ft

     Length of the building is = ?  = x ft

     using similarity of triangles   we get  length of the stick/height of the building =  shadow of the stick/shadow of the building

 substituting the values  we get   13/12/x = 16/12/85

                                  13/12*x = 16/12*85

                                    x = 13*12*85/12*16

                                      = 13*85/16 = 69.06  ft  = 69.1  ft