Ответ:

  1. −7·(−7+15):28+3 = −7·8:28+3 = −56:28+3 = −2+3 = 1.
  2. 7,4·(−7−3):5 = 7,4·(−10):5 = −74:5 = −14,8.
  3. −4/7·(−1/2) = 4/14 = 2/7.
  4. (1/5−3/4)·(−4) = (4/20−15/20)·(−4) = −11/20·(−4) = 11/5.
  5. (−2+3,6−10):(−7)·(−5) = (−8,4):(−7)·(−5) = 1,2·(−5) = −6.
  6. −3,1·(−0,1)−3,3·0,01−0,3·(−1,2) = 0,31−0,033−(−0,36) = 0,637.
  7. (5,7−9,8+1,4−3,5+6,2)·(−2) = 0·(−2) = 0.