GSEB Solutions for Class 7 Mathematics – Revision 1 (Sem – II) (English Medium)
GSEB SolutionsMathsScience
Revision 1
Solution 1(1):
c. 56
[(-5)2]3
= (-5)2×3
=(-5)6
= 56
Hint: When a negative number is raised by an even number, the product is always positive.
Solution 1(2):
b. x5
x3 × x2
= x3 + 2
= x5
Solution 1(3):
Solution 1(4):
a. 23
(-12)3
= (-6 × 2)3
= (-6)3 × 23
Solution 1(5):
a. 76
712 ÷ (73)2
= 712 ÷ (73×2)
= 712 ÷ 76
= 712-6
= 76
Solution 1(6):
b. a12b6c3
(a4b2c)3
= (a4×3)(b2×3)(c3)
= a12b6c3
Solution 1(7):
Solution 1(8):
b. m3n3
m2n × n2m
= m2+1 × n1+2
= m3n3
Solution 2(1):
m4 × m5 ÷ m3 (m ≠ 0)
= m4+5 ÷ m3
= m9 ÷ m3
= m9 – 3
= m6
Solution 2(2):
a10 ÷ a13 × a (a ≠ 0)
= a10-13 × a
= a-3 × a
= a-3+1
= a-2
= 1/a2
Solution 2(3):
(xy)3 ÷ [x4 × (y2)3] (x ≠ 0, y ≠ 0)
= x3y3 ÷ [x4 × (y2×3)]
= x3y3 ÷ x4y6
= x3-4y3-6
= x-1y-3
= 1/xy3
Solution 3(1):
36 × (33)2 ÷ 310
= 36 × 33×2 ÷ 310
= 36 × 36 ÷ 310
= 36+6 ÷ 310
= 312-10
= 32
= 9
Solution 3(2):
[(-5)3 ]3 ÷ [(-5)2]3
= (-5)3×3 ÷ (-5)2×3
= (-5)9 ÷ (-5)6
= (-5)9-6
= (-5)3
= (-5) × (-5) × (-5)
= (-125)
Solution 3(3):
Solution 3(4):
(22)6 ÷ (22 × 24)
= 22×6 ÷ (22+4)
= 212 ÷ (26)
= 212-6
= 26
= 64
Solution 4:
Solution 5(1):
Solution 5(2):
Solution 5(3):
Solution 6(1):
10 – {10 + (6 ÷ 2)}
= 10 – {10 + 3}
= 10 – {13}
= 10 – 13
= (-3)
Solution 6(2):
5 × [7 + (4 × 3)]
= 5 × [7 + 12]
= 5 × [19]
= 5 × 19
= 95
Solution 6(3):
7y – [-{-(-7x)}]
= 7y – [-{7x}]
= 7y – [-7x]
= 7y +7x
Solution 6(4):
2a – {a + 2(5 – b)}
= 2a – {a + 10 – 2b}
= 2a – a – 10 + 2b
= a – 10 + 2b
= a + 2b – 10
Solution 6(5):
[3y – (x + 2y)] – [x + (2x – y)]
= [3y – x – 2y] – [x + 2x – y]
= [y – x] – [3x – y]
= y – x – 3x + y
= y + y – x – 3x
= 2y – 4x
Solution 6(6):
Solution 6(7):
[3a – a(2 – a)] – a
= [3a – 2a + a2] – a
= [a + a2] – a
= a + a2 – a
= a2
Solution 6(8):
[(10 ÷ 5) ÷ (45 ÷ 9)]
= 2 ÷ 5
= 2/5
Solution 6(9):
{(7 × 2) – 4} – [8 – (10 ÷ 2)]
= {(14) – 4} – [8 – (5)]
= {10} – [3]
= 7
Solution 6(10):
m + [n + {2m – (m + 2n)}]
= m + [n + {2m – m – 2n}]
= m + [n + {m – 2n}]
= m + [n + m – 2n]
= m + [m – n]
= m + m – n
= 2m – n