(a) Find the ratio a : b : c
(b) Find the values of a,b and c.
3. Suppose that a, b and c (where a< b < c ) are 3 consecutive even numbers. If a : c = 5 : 6, find the numbers a, b and c.
4.Gary stands in front of a lamppost at B . He puts a mirror M on the ground and sees the reflection of the top of the lamppost C as shown inthe figure. It is known that ∠AMB = ∠CKD.
ab =1.5 m, CD = 6m and BD =15m.
(a) Which triangle is similar to △ABM?
(b) fIND THE RATIO BM : DM.
(c) Hence find the length of DM.
更新1:
係3條,Sorry / \
更新2:
有式, +5點!!!
更新3:
你可以吾答第4條- ]
更新4:
我改一改第4條, 4.The ratio of the number of marbles owned by Susan to the number of marbles owned by Teresa is 5 : 2. Susan has n marbles. If Susan gives 18 of her own marbles to Teresa, both of them will have the same number of marbles.Find n.