3
SOLUCIONES. PROPUESTA DE EVALUACIÓN. PRUEBA A
MATERIAL FOTOCOPIABLE
/ © Oxford University Press España, S. A.
Matemáticas 1.º ESO
1.
2.
a) |–12| = 12
c) op (–5) = 5
b) op (23) = –23
d) |+4| = 4
3.
a) (–12) – (+7) = –12 – 7 = –19
b) (+12) + (–7) = 12 – 7 = 5
c) (+7) – (+12) = 7 – 12 = –5
d) (–7) – (–12) = –7 + 12 = 5
4. a) (–18) : (+3) = –6
b) (+5) · (–3) = –15
c) (+7) · (+2) = 14
d) (–16) : (–2) = 8
5. a) 2 – 5 · 2 = 2 – 10 = – 8
b) 8 + (–4) · 3 – (–1) = 8 – 12 + 1 = –3
c) –5 – 4 · (–2) – (–6) = –5 + 8 + 6 = 9
d) 14 + (3 – 5) · 6 – 2 · (–5) = 14 + (–2) · 6 + 10 = 14 – 12 + 10 = 12
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SOLUCIONES. PROPUESTA DE EVALUACIÓN. PRUEBA B
1.
(3 – 4) = –1
op(4) = –4 |–7| = 7
(–1 – 1) = –2
op(2) + |–3| = –2 + 3 = 1
op (4) < (–1 – 1) < (3 – 4) < op(2) + |–3| < |–7|
2.
a) –12 + 5 – (+7) – 1 = –12 + 5 – 7 – 1 = –7 – 7 – 1 = –14 – 1 = –15
b) –5 – (–2) + (–7) + 3 = –5 + 2 – 7 + 3 = –3 – 7 + 3 = –10 + 3 = –7
c) 7 – 5 – (+12) – (–3) = 7 – 5 – 12 + 3 = 2 – 12 + 3 = –10 + 3 = –7
d) (–6) – 2 + (–3) + 5 = –6 – 2 – 3 + 5 = –8 – 3 + 5 = –11 + 5 = –6
3.
a) (–8) · (+3) : (–6) = –24 : (–6) = 4
b) 5 · (–6) : (–2) = –30 : (–2) = 15
c) (+7) ·(–3) · (+2) = – 21 · 2 = –42
d) 24 : (–3) : (–2) = –8 : (–2) = 4
4.
a) –15 – 4 · (–3) – (–8) = –15 + 12 + 8 = 5
b) 8 + (–14) · 2 – (–5) · 3 = 8 – 28 + 15 = –5
5.
–12 + (5 – (2 – 4 · 3) : (–5) + 1) – 3 · (–2) =
= –12 + (5 – (2 – 12) : (–5) + 1) – 3 · (–2) =
= –12 + (5 – (–10) : (–5) + 1) – 3 · (–2) =
= –12 + (5 – 2 + 1) – 3 · (–2) =
= –12 + 4 – 3 · (–2) =
= –12 + 4 + 6 =
= –8 + 6 = –2
