Practice Math Class 7th to 9th
Mathematics Practice Set
1. Probability (āϏāĻŽā§āĻāĻžā§ąāύāĻž)
Q1. A box contains 4 red pencils, 6 blue pencils and 5 green pencils. What is the probability of picking a green pencil at random ? (āĻĒā§ā§°āĻļā§āύ ā§§āĨ¤ āĻāĻāĻž āĻŦāĻžāĻāĻāϤ ā§ĒāĻāĻž ā§°āĻāĻž, ā§ŦāĻāĻž āύā§āϞāĻž āĻā§°ā§ ā§ĢāĻāĻž āϏā§āĻāĻā§āϝāĻŧāĻž āĻĒā§āĻā§āĻāĻŋāϞ āĻāĻā§āĨ¤ āϝāĻžāĻĻā§āĻā§āĻāĻŋāĻāĻāĻžā§ąā§ āĻāĻāĻž āϏā§āĻāĻā§āϝāĻŧāĻž āĻĒā§āĻā§āĻāĻŋāϞ āĻāĻ āĻžā§° āϏāĻŽā§āĻāĻžā§ąāύāĻž āĻāĻŋāĻŽāĻžāύ ?)
Solution (āϏāĻŽāĻžāϧāĻžāύ):
Total pencils (āĻŽā§āĻ āĻĒā§āĻā§āĻāĻŋāϞ)
= 4 + 6 + 5
= 15
Green pencils (āϏā§āĻāĻā§āϝāĻŧāĻž āĻĒā§āĻā§āĻāĻŋāϞ)
= 5
Probability (āϏāĻŽā§āĻāĻžā§ąāύāĻž)
Probability = Favourable Outcomes / Total Outcomes = 5/ 15 = 1/3
Ans (āĻāϤā§āϤ⧰): Probability = 1/3 (āϏāĻŽā§āĻāĻžā§ąāύāĻž = ā§§/ā§Š)
2. Algebraic Expression (āĻŦā§āĻāĻāĻžāĻŖāĻŋāϤāĻŋāĻ ā§°āĻžāĻļāĻŋ)
Q2. Simplify: āϏ⧰āϞ āĻā§°āĻāĻ 4(3x − 2) − 2(2x + 5)
Solution (āϏāĻŽāĻžāϧāĻžāύ):
4(3x−2) − 2(2x+5)
Open the brackets (āĻŦā§ā§°ā§āĻā§āĻ āĻā§āϞāĻ) =12x − 8 − 4x − 10
Combine like terms (āĻāĻā§ āϧ⧰āĻŖā§° āĻĒāĻĻ āĻāĻā§āϞāĻ āĻā§°āĻ) = (12x − 4x) − (8 + 10)
Ans (āĻāϤā§āϤ⧰): 8x − 18
3. Linear Equation(āϏ⧰āϞ āϏāĻŽā§āĻā§°āĻŖ)
Q3. Solve for x : (x ā§° āĻŽāĻžāύ āĻāϞāĻŋāϝāĻŧāĻžāĻāĻāĻ): 3x − 9 = 18
Solution (āϏāĻŽāĻžāϧāĻžāύ):
3x − 9 = 18
Add 9 to both sides (āĻĻā§āϝāĻŧā§āĻĢāĻžāϞ⧠⧝ āϝā§āĻ āĻā§°āĻ) = 3x = 18 + 9 = 27
Divide by 3 (ā§Š āĻĻā§āĻŦāĻžā§°āĻž āĻāĻžāĻ āĻā§°āĻ) : x = 27/3 = 9
Ans (āĻāϤā§āϤ⧰): x = 9
4. Perimeter of Rectangle (āĻāϝāĻŧāϤāĻā§āώā§āϤā§ā§°ā§° āĻĒā§°āĻŋāϏā§āĻŽāĻž)
Q4. A rectangular table is 12 cm long and 7 cm wide. Find its perimeter. āĻĒā§ā§°āĻļā§āύ ā§ĒāĨ¤ āĻāĻāĻž āĻāϝāĻŧāϤāĻā§āώā§āϤā§ā§°ā§° āĻĻā§ā§°ā§āĻā§āϝ 12 cm āĻā§°ā§ āĻĒā§ā§°āϏā§āĻĨ 7 cmāĨ¤ āĻāϝāĻŧāĻžā§° āĻĒā§°āĻŋāϏā§āĻŽāĻž āύāĻŋā§°ā§āĻŖāϝāĻŧ āĻā§°āĻāĨ¤
Solution (āϏāĻŽāĻžāϧāĻžāύ):
Formula (āϏā§āϤā§ā§°) : Perimete r= 2(Length+Width) = 2(12+7) = 2×19 =
Ans (āĻāϤā§āϤ⧰): Perimeter = 38 cm (āĻĒā§°āĻŋāϏā§āĻŽāĻž = ā§Šā§Ž āĻā§āĻŽāĻŋ)
5. Discount(ā§°ā§āĻšāĻžāĻ)
Q5. A jacket is marked at $120. During a sale, it is reduced by 25%. Find the discount and the sale price. āĻĒā§ā§°āĻļā§āύ ā§ĢāĨ¤ āĻāĻāĻž āĻā§āĻā§āĻā§° āĻŽā§āϞā§āϝ $120āĨ¤ āĻŦāĻŋāĻā§ā§°ā§ā§° āϏāĻŽāϝāĻŧāϤ āĻāϝāĻŧāĻžāϤ 25% ā§°ā§āĻšāĻžāĻ āĻĻāĻŋāϝāĻŧāĻž āĻšā§āĻā§āĨ¤ ā§°ā§āĻšāĻžāĻā§° āĻĒā§°āĻŋāĻŽāĻžāĻŖ āĻā§°ā§ āĻŦāĻŋāĻā§ā§°āϝāĻŧ āĻŽā§āϞā§āϝ āύāĻŋā§°ā§āĻŖāϝāĻŧ āĻā§°āĻāĨ¤
Solution (āϏāĻŽāĻžāϧāĻžāύ):
Marked Price (āĻŽā§āϞ āĻŽā§āϞā§āϝ) = $120
Discount (ā§°ā§āĻšāĻžāĻ) = 25/100 × 120 =
Sale Price (āĻŦāĻŋāĻā§ā§°āϝāĻŧ āĻŽā§āϞā§āϝ) = 120 − 30 =
Ans (āĻāϤā§āϤ⧰): Discount (ā§°ā§āĻšāĻžāĻ) = $30, Sale Price (āĻŦāĻŋāĻā§ā§°āϝāĻŧ āĻŽā§āϞā§āϝ) = $90