Fluidité · Pack A
8.2 Ratio and Rates
Répondez à chaque question. Montrez les calculs si nécessaire.
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Simplify the ratio $16:36$ fully. State the HCF you used.
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Simplify the ratio $21:14:35$ fully.
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Write 6 hours out of 24 hours as a percentage.
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In a bag there are 5 strawberry sweets and 15 orange sweets. Write the ratio of strawberry to orange in its simplest form.
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Find 60% of 600 g.
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Write $\dfrac{3}{4}$ as a percentage.
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12 apples cost 3.00 chf. Find the cost of 1 apple.
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Fill in the missing value so that $3:5$ is equivalent to $\square:20$.
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Increase 100 chf by 25%.
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Decrease 125 chf by 25%.
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Simplify the ratio 270 mm : 36 cm : 45 cm.
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Share 60 chf in the ratio $2:3$.
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A bag of 20 sweets contains 13 raspberry sweets; the rest are pineapple. (a) Write the ratio raspberry : pineapple in simplest form. (b) What percentage of the sweets are pineapple?
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12 chocolate bars cost 3.00 chf. How much would 30 chocolate bars cost at the same rate?
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12 chocolate bars cost 3.00 chf. How many bars can be bought for 4.50 chf?
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A car travels 240 km in 3 hours. Find its average speed in km/h and km/min.
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A water tank fills at 6 L/min. How many litres in (a) 12 minutes? (b) 2 hours?
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Find the unit rate: 15 chf for 6 kg of fruit.
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An item that cost 80 chf is now 60 chf. Find the percentage decrease.
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A salary of 4000 chf is increased by 8%. Find the new salary.
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In a 3-leg relay, Stefania ran $\dfrac{2}{5}$ of the course, Jan ran 35% of the course, and René ran the rest. What percentage did René run?
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A bike is on sale for 590 chf. This is a 26% discount on the original price. What was the original price? Give your answer to 2 decimal places.
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If $x:y = 4:5$ and $x:z = 3:7$, find the ratio $y:z$ in its simplest form.
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Out of 2000 competitors, 1650 finished the race. The ratio of female : male finishers is $20:13$. Find the number of male finishers and the number of female finishers.
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You earn 100 chf a week. Your boss gives you a 25% pay increase. The following week your new pay is cut by 25%. How much do you earn now?
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Shop A: 12 bars for 3.00 chf. Shop B: 12 bars for 3.50 chf, plus 3 free bars. Which shop offers better value per bar?
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A submarine is at $-80$ m. It rises by 25% of its current depth (towards the surface). What is its new depth?
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Which of these ratios are equivalent to $3:4$? Pick all that apply.\nA: $9:12$, B: $15:18$, C: $21:28$.
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A car travels 270 km in 3 hours. (a) Find the speed in km/h. (b) Convert to m/s.
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A price of 100 chf is increased by 25% then decreased by 20%. What is the final price?
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A long-sleeve shirt has 8 front buttons and 2 cuff buttons; a short-sleeve shirt has 6 front buttons and no cuff buttons. The factory uses 10 times as many front buttons as cuff buttons in total. Find the ratio of long-sleeve to short-sleeve shirts produced.
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A price is increased by 20% and then decreased by 25%. Find the single percentage change equivalent to these two changes.
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A jacket is reduced by 20% in a January sale, then by a further 25% in February. After both reductions it costs 60 chf. Find the original price.
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In a class of 40 pupils, the ratio of pupils who walk to school to those who cycle is $8:5$. $\dfrac{1}{4}$ of the class take the bus and 4 pupils take the train. How many walk?
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In a school the ratio of Year 7 : Year 8 : Year 9 is $5:4:3$. Year 7 has 100 pupils. (a) How many pupils are in Year 9? (b) What percentage of the school is in Year 8? Give your answer to 1 d.p.
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A car depreciates by 15% in its first year and by 10% each subsequent year. If the car cost £20000 new, find its value after 3 years (to nearest £).
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Currency: 1 chf = 1.04 EUR. A shopkeeper charges 2% commission on euro purchases. If a tourist exchanges 250 chf, how many euros do they receive?
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A 10-litre solution is 60% acid. How much pure water must be added to dilute it to 40% acid?
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Three friends share an inheritance in the ratio $2:3:5$. The eldest receives £1200 more than the youngest. Find each share.
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Two prices fell by the same percentage. The first fell from £400 to £320; the second fell from £600 to $x$. Find $x$.