NEGATIVE   NUMBERS

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          -15            -12           ___           -6            -3           ___          3           6

answer:      -9         0

 

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             -40             -30            __            -10               0                10               20         ___        ___








answer:      -20         30       40










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     __         -30           __          -22          __         -14         -10            -6          -2       __       6






answer:     -34       -26       -18         2