Mathematics for IGCSE & O level - Similarity (Section 3 - No. 1)
Josh bought a set of table mats. The set contained mats of three different sizes. The smallest one was 5 cm by 8 cm, the middle one was an enlargement of the smallest by scale factor 3, and the shorter side of the largest mat was 25cm. Find the dimensions of the two larger mats.
15 cm by 24 cm and 75 cm by 120 cm
15 cm by 24 cm and 12.5 cm by 20 cm
25 cm by 40 cm and 75 cm by 120 cm
15 cm by 25 cm and 75 cm by 120 cm
Uitleg
Middle mat = 5 * 3 by 8 * 3 = 15 cm by 24 cm. Scale factor of largest mat = 25 / 5 = 5, therefore 8*5=40. Largest mat is 25 cm by 40 cm.