Hard Arithmetic Puzzles

#4463: 9 _ 6 _ 5 _ 3 = 19 hard #4466: 9 _ 6 _ 5 _ 2 = 15 hard #4467: 9 _ 6 _ 6 _ 4 = 18 hard #4468: 9 _ 6 _ 6 _ 9 = 13 hard #4471: 9 _ 6 _ 8 _ 4 = 12 hard #4472: 9 _ 6 _ 8 _ 3 = -7 hard #4475: 9 _ 6 _ 8 _ 1 = 13 hard #4476: 9 _ 6 _ 8 _ 2 = 14 hard #4479: 9 _ 6 _ 8 _ 3 = 15 hard #4481: 9 _ 6 _ 8 _ 4 = 16 hard #4483: 9 _ 6 _ 8 _ 5 = 17 hard #4485: 9 _ 6 _ 8 _ 6 = 18 hard #4487: 9 _ 6 _ 8 _ 7 = 19 hard #4489: 9 _ 6 _ 8 _ 8 = 20 hard #4491: 9 _ 6 _ 9 _ 3 = 11 hard #4492: 9 _ 6 _ 9 _ 6 = 13 hard #4500: 9 _ 7 _ 3 _ 2 = 19 hard #4501: 9 _ 7 _ 3 _ 3 = 18 hard #4502: 9 _ 7 _ 3 _ 5 = 16 hard #4503: 9 _ 7 _ 3 _ 6 = 15 hard #4504: 9 _ 7 _ 3 _ 7 = 14 hard #4505: 9 _ 7 _ 3 _ 9 = 12 hard #4510: 9 _ 7 _ 9 _ 2 = 14 hard #4512: 9 _ 8 _ 2 _ 4 = 13 hard #4516: 9 _ 8 _ 3 _ 4 = 15 hard #4517: 9 _ 8 _ 3 _ 6 = 13 hard #4521: 9 _ 8 _ 3 _ 6 = -7 hard #4522: 9 _ 8 _ 3 _ 4 = 20 hard #4524: 9 _ 8 _ 3 _ 6 = 18 hard #4525: 9 _ 8 _ 3 _ 7 = 17 hard #4526: 9 _ 8 _ 3 _ 8 = 16 hard #4527: 9 _ 8 _ 3 _ 9 = 15 hard #4528: 9 _ 8 _ 4 _ 5 = 19 hard #4533: 9 _ 8 _ 4 _ 8 = -7 hard #4534: 9 _ 8 _ 4 _ 9 = -9 hard #4535: 9 _ 8 _ 4 _ 1 = 19 hard #4536: 9 _ 8 _ 4 _ 1 = 17 hard #4537: 9 _ 8 _ 4 _ 2 = 20 hard #4538: 9 _ 8 _ 4 _ 2 = 16 hard #4540: 9 _ 8 _ 4 _ 4 = 14 hard #4541: 9 _ 8 _ 4 _ 5 = 13 hard #4542: 9 _ 8 _ 4 _ 6 = 12 hard #4543: 9 _ 8 _ 4 _ 7 = 11 hard #4546: 9 _ 8 _ 5 _ 4 = 19 hard #4548: 9 _ 8 _ 6 _ 3 = 13 hard #4549: 9 _ 8 _ 6 _ 3 = -7 hard #4553: 9 _ 8 _ 6 _ 1 = 13 hard #4557: 9 _ 8 _ 6 _ 4 = 16 hard