3
SOLUCIONES. ACTIVIDADES DE REFUERZO
MATERIAL FOTOCOPIABLE
/ © Oxford University Press España, S. A.
Matemáticas 1.º ESO
1.
a) Signo: – Parte numérica: 3
b) Signo: + Parte numérica: 4
c) Signo: – Parte numérica: 7
d) Signo: + Parte numérica: 5
2.
a) –3 < – 1 < 0 < 4 < 5
b) – 9 < –7 < –4 < –2 < 1 < 3
3.
a) op (–6) = 6
c) |–7| = 7
b) |4| = 4
d) op (19) = –19
4.
a) (–9) + (+12) = –9 + 12 = 3
b) (+6) – (–2) = 6 + 2 = 8
c) (–4) + (–7) = –4 – 7 = –11
d) (+12) + (–15) = 12 – 15 = –3
e) (–9) + (+5) = –9 + 5 = –4
f) (–8) – (–6) = –8 + 6 = –2
5.
a) 12 – 5 – 9 + 3 = 7 – 9 + 3 = –2 + 3 = 1
b) –10 + 4 + 6 – 15 = –6 + 6 – 15 = –15
c) –7 – 9 + 5 – 1 = –16 + 5 – 1 = –12
d) 4 + 8 – 10 – 1 = 12 – 10 – 1 = 2 – 1 = 1
e) 5 – 7 + 1 – 3 = –2 + 1 – 3 = –1 – 3 = –4
f) –8 + 15 – 4 – 3 = 7 – 4 – 3 = 3 – 3 = 0
6.
a) (+5) · (–3) = –15
b) (+18) : (–6) = –3
c) (–7) · (–2) = 14
d) (–12) : (–4) = 3
e) (–15) : (+5) = –3
f) (–6) · (+4) = –24
7.
a) 4 + (–5) · 3 = 4 – 15 = – 11
b) –12 – 18 : (–3) = –12 + 6 = –6
c) 6 · 2 + (–4) · 5 = 12 – 20 = –8
d) –9 + 3 · (–2) + 10 = –9 – 6 + 10 = –5
8.
a) 4 + (5 – 9) · 4 – 3 = 4 + (–4) · 4 – 3 =
= 4 – 16 – 3 = –12 – 3 = –15
b) –12 – (8 – 12) : 2 + 4 = –12 – (–4) : 2 + 4 =
= –12 + 2 + 4 = –6
9.
200 – 3 · 75 = 200 – 225 = – 25
Debe 25 euros.
10.
–17 + 3 · (–3) = –17 – 9 = –26
La temperatura será de –26 ºC.
1.
a) Op (|–2|) = Op (2) = –2
b) op(|op (3)|) = op(|–3|) = op (3) = –3
2.
Sí. El 0.
3.
a) +4
b) +4
4.
a) –12 – |7 – 10| · 3 + 12 : (–6) + 4 =
= –12 – |–3| · 3 + 12 : (–6) + 4 =
= –12 – 3 · 3 + 12 : (–6) + 4 =
= –12 – 9 – 2 + 4 = –19
b) 3 – (14 : |3 – 5| – 9) + (–3) · (–5) =
= 3 – (14 : |–2| – 9) + (–3) · (–5) =
= 3 – (7 – 9) + (–3) · (–5) =
= 3 – (–2) + (–3) · (–5) =
= 3 + 2 + 15 = 20
5.
a) –25 + (14 – 4 ·(12 + 5 · (–4) – 3)) + 3 · (–2) =
= –25 + (14 – 4 ·(12 – 20 – 3)) + 3 · (–2) =
= –25 + (14 – 4 · (–11)) + 3 · (–2) =
= –25 + (14 + 44) + 3 · (–2) =
= –25 + 58 + 3 · (–2) =
= –25 + 58 + – 6 = 27
b)
16 : (2 – (4 + 3 · 2)) + 5 · (4 + (–3)) – 1 =
= 16 : (2 – (4 + 6)) + 5 · (4 – 3) – 1 =
= 16 : (2 – 10) + 5 · 1 – 1 =
= 16 : (–8) + 5 – 1 =
= –2 + 5 – 1 = 2
6.
a) (–3)
75
→ –
d) (–4)
3
→ –
b) (–1)
9
→ –
e) (–3)
125
→ –
c) (–5)
42
→ +
f) (–10)
350
→ +
7.
a) 3
b) 6
c) 3
8.
a) ((–4) · 2)
3
= (–8)
3
= –512
b) ((–16) : (– 8))
6
= 2
6
= 64
c) (15 : (–3))
3
= (–5)
3
= –125
d) (125 : (–5))
2
= (–25)
2
= 625
e) ((–42) : 42)
13
= (–1)
13
= –1
f) (4 · (–3))
2
= (–12)
2
= 144
9.
a) –12 – (–2)
2
+ 7 + (–3)
3
=
= –12 – 4 + 7 – 27 = –36
b) (–7)
2
+ (4 – 5)
7
+ (–2) =
= 49 + (–1)
7
– 2 =
= 49 – 1 – 2 = 46
c) (–3)
3
+ 2 · (–3) + (–5) =
= –27 – 6 – 5 = –38
d) –5 + (6 – 8)
3
– (–4)
2
=
= –5 + (–2)
3
– 16 =
= –5 – 8 – 16 = –29
10.
3 · (–2)
2
+ 5 · (4 – 7)
3
+ 4 · (6 – (–2)
3
· 3) + 1 =
= 3 · 4 + 5 · (–3)
3
+ 4 · (6 + 8 · 3) + 1 =
= 3 · 4 + 5 · (–27) + 4 · (6 + 24) + 1 =
= 3 · 4 – 135 + 4 · 30 + 1 =
= 12 – 135 + 120 + 1 = –2
3
SOLUCIONES. ACTIVIDADES DE AMPLIACIÓN
