Ratio and Scale Flashcards
(11 cards)
Simplify the ratio
12 : 16
Simplify the ratio 12 : 16
Answer: 3 : 4
Write the ratio in the form 1 : n
8 : 24
Write the ratio 8 : 24 in the form 1 : n
Answer: 1 : 3
Divide £90 in the ratio 2 : 3.
How much does each person get?
Divide £90 in the ratio 2 : 3
Total parts = 2 + 3 = 5
Each part = £90 ÷ 5 = £18
Answer: £36 and £54
If a recipe uses flour and sugar in the ratio 3 : 2 and you have 180g of flour, how much sugar do you need?
Flour : Sugar = 3 : 2, Flour = 180g
Each part = 180 ÷ 3 = 60g
Sugar = 2 × 60 = 120g
A map has a scale of 1 : 50,000. If two towns are 8 cm apart on the map, what is the actual distance between them in km?
Map scale 1 : 50,000, Map distance = 8 cm
Actual distance = 8 × 50,000 = 400,000 cm
Convert to km: 400,000 ÷ 100,000 = 4 km
A class of students contains boys and girls in the ratio 5 : 4. If there are 36 students in total, how many are boys?
Boys : Girls = 5 : 4, Total = 36
Total parts = 5 + 4 = 9
Each part = 36 ÷ 9 = 4
Boys = 5 × 4 = 20
A model car is built to a scale of 1 : 20. If the model is 25 cm long, what is the real length of the car in metres?
Scale 1 : 20, Model = 25 cm
Real length = 25 × 20 = 500 cm = 5 metres
In a mixture of red and blue paint in the ratio 7 : 3, how much red paint is needed if you use 90 litres in total?
Red : Blue = 7 : 3, Total = 90 litres
Total parts = 10
Each part = 90 ÷ 10 = 9
Red paint = 7 × 9 = 63 litres
The ratio of the angles in a triangle is 3 : 4 : 5. Find the size of each angle.
Angles ratio = 3 : 4 : 5
Total parts = 12
Each part = 180° ÷ 12 = 15°
Angles = 3×15 = 45°, 4×15 = 60°, 5×15 = 75°
A photograph measures 10 cm by 15 cm. It is enlarged by a scale factor of 2. What are the dimensions of the new photo?
Original photo = 10 cm × 15 cm, Scale factor = 2
New size = 10×2 = 20 cm, 15×2 = 30 cm
Answer: 20 cm × 30 cm
How do you simplify a ratio?
Divide all parts by the highest common factor
