Arya Study Centre

Here are 100 One-Word Question Answers (Class 6–8 Science) : Unit of force? — Newton Process by which plants make food? — Photosynthesis Gas needed for breathing? — Oxygen Closest planet to the Sun? — Mercury SI unit of length? — Metre Device to measure temperature? — Thermometer Hardest natural substance? — Diamond Centre of an atom? — Nucleus Force that pulls objects to Earth? — Gravity Liquid changing into vapour? — Evaporation Vitamin from sunlight? — VitaminD Red planet? — Mars Instrument to see microorganisms? — Microscope Main gas in air? — Nitrogen Unit of electric current? — Ampere Organ that pumps blood? — Heart Green pigment in leaves? — Chlorophyll Vapour changing into liquid? — Condensation Largest planet? — Jupiter Energy from the Sun? — Solar Device to measure time? — Clock Framework of bones? — Skeleton Unit of mass? — Kilogram Gas used in photosynthesis? — CarbonDioxide Sprouting of seed? — Germination Smallest unit of life? — Cell Device to...

10 percentage questions with solutions. 1. Find 25% of 200. Solution: 25% of 200  = (25/100) x 200 = 50 Explanation: Percentage means “per hundred.” So we multiply the number by the given percentage and divide by 100. 2. Find 10% of 350. Solution: 10% of 350 = = (10/100) X 350   = 35 Explanation: 10% means one-tenth of a quantity. 3. Find 15% of 80. Solution: 15% of 80 = = (15/100) X 80   = 12 Explanation: Convert the percentage into a fraction and multiply. 4. What percentage of 50 is 20? Solution: Percentage = (x/100) x 50 = 20 X = (20/50) x 100 = 40% Explanation: Divide the part by the whole and multiply by 100. 5. What percentage of 400 is 60? Solution: Percentage = (60/400) x 100 = 15% Explanation: This shows how much 60 is out of 400. 6. A student scored 45 marks out of 60. Find the percentage of marks obtained. Solution: Percentage = (45/60) x 100 = 75% Explanation: Marks obtained ÷ Total marks × 100 gives the percentage...

Maths : Ratio 1. Write the ratio of 3 apples to 5 apples. Answer: 3 : 5 Explanation: Ratio compares quantities of the same type. So, apples to apples = 3 : 5. 2. Express the ratio 12 : 18 in its simplest form. Answer: 2 : 3 Explanation: Find the HCF of 12 and 18, which is 6. Divide both terms by 6: 12 ÷ 6 = 2, 18 ÷ 6 = 3 So the simplest form is 2 : 3. 3. The ratio of boys to girls in a class is 4 : 5. If there are 20 boys, how many girls are there? Answer: 25 girls Explanation: 4 parts = 20 boys 1 part = 20 ÷ 4 = 5 Girls = 5 parts = 5 × 5 = 25 4. Divide ₹120 in the ratio 2 : 3. Answer: ₹48 and ₹72 Explanation: Total parts = 2 + 3 = 5 Value of 1 part = 120 ÷ 5 = 24 First share = 2 × 24 = ₹48 Second share = 3 × 24 = ₹72 5. The ratio of red balls to blue balls is 7 : 9. If there are 63 red balls, find the number of blue balls. Answer: 81 blue balls Explanation: 7 parts = 63 1 part = 63 ÷ 7 = 9 Blue balls = 9 parts = 9 × 9 = 81 6. The ratio of length to breadth of a rectangle is 5 : 3. If ...