Arithmetic Operator Puzzles

#1489: 3 _ 8 _ 6 _ 8 = 12 medium #1490: 3 _ 8 _ 6 _ 8 = -4 medium #1491: 3 _ 8 _ 6 _ 9 = 13 hard #1492: 3 _ 8 _ 6 _ 9 = -5 medium #1493: 3 _ 8 _ 7 _ 4 = 17 hard #1494: 3 _ 8 _ 8 _ 4 = 19 hard #1495: 3 _ 8 _ 8 _ 2 = 20 hard #1496: 3 _ 8 _ 9 _ 6 = 15 hard #1497: 3 _ 8 _ 9 _ 6 = -9 hard #1498: 3 _ 8 _ 9 _ 6 = 16 hard #1499: 3 _ 9 _ 2 _ 3 = 9 medium #1500: 3 _ 9 _ 2 _ 3 = -3 medium #1501: 3 _ 9 _ 2 _ 6 = 9 medium #1502: 3 _ 9 _ 2 _ 3 = 2 easy #1503: 3 _ 9 _ 2 _ 6 = 1 easy #1504: 3 _ 9 _ 3 _ 2 = 9 medium #1505: 3 _ 9 _ 3 _ 5 = 18 hard #1506: 3 _ 9 _ 3 _ 2 = -3 medium #1507: 3 _ 9 _ 3 _ 4 = -9 hard #1508: 3 _ 9 _ 3 _ 1 = 2 easy #1509: 3 _ 9 _ 3 _ 2 = 3 easy #1510: 3 _ 9 _ 3 _ 3 = -2 medium #1511: 3 _ 9 _ 3 _ 4 = -3 medium #1512: 3 _ 9 _ 3 _ 5 = 6 medium #1513: 3 _ 9 _ 3 _ 6 = 7 medium #1514: 3 _ 9 _ 3 _ 6 = -5 medium #1515: 3 _ 9 _ 3 _ 7 = -6 medium #1516: 3 _ 9 _ 3 _ 8 = 9 medium #1517: 3 _ 9 _ 3 _ 8 = -7 hard #1518: 3 _ 9 _ 3 _ 9 = 10 medium #1519: 3 _ 9 _ 3 _ 9 = -8 hard #1520: 3 _ 9 _ 4 _ 6 = 9 medium #1521: 3 _ 9 _ 4 _ 3 = -9 hard #1522: 3 _ 9 _ 4 _ 6 = -3 medium #1523: 3 _ 9 _ 4 _ 3 = 4 easy #1524: 3 _ 9 _ 4 _ 6 = 8 easy #1525: 3 _ 9 _ 5 _ 3 = 18 hard #1526: 3 _ 9 _ 5 _ 9 = 15 hard #1527: 3 _ 9 _ 5 _ 3 = 5 easy #1528: 3 _ 9 _ 5 _ 6 = 10 medium #1529: 3 _ 9 _ 6 _ 4 = 9 medium #1530: 3 _ 9 _ 6 _ 8 = 15 hard #1531: 3 _ 9 _ 6 _ 4 = -3 medium #1532: 3 _ 9 _ 6 _ 8 = -9 hard #1533: 3 _ 9 _ 6 _ 1 = 3 easy #1534: 3 _ 9 _ 6 _ 2 = 1 easy #1535: 3 _ 9 _ 6 _ 3 = 5 easy #1536: 3 _ 9 _ 6 _ 3 = -1 easy