Overview: 1 questions will be solved this time.Among them
           ☆1 equations

[ 1/1 Equation]
    Work: Find the solution of equation 320/3.5+20*d+320*0.3*6/3.5^2 = 1.2*(130+0.5*0.5*19+2*19*0.5) .
    Question type: Equation
    Solution:
    the solutions is:
        d≈2.302551 , keep 6 decimal places    
    There are 1 solution(s).

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