Explicație pas cu pas:
(-7/-12 + 3/8) • (-8/-15) + (-7/-24) • (16/21) =
(-)/(-) = (+)
(7/12 + 3/8) • 8/15 + 7/24 • 16/21 =
(2•7/24 + 3•3/24) • 8/15 + 1/24 • 16/3=
(14/24 + 9/24) • 8/15 + 1/3 • 2/3 =
23/24 • 8/15 + 2/9 =
23/3 • 1/15 + 2/9 =
23/45 + 2/9 =
23/45 + 2•5/45 =
23/45 + 10/45 =
33/45 =
11/15
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