A convex lens and a concave lens, each having same focal length of `25 cm`, are put in contact to form a combination of lenses. The power in diopters of the combination is

A convex lens and a concave lens, each having same focal length of 25 cm, are put in contact to form a combination of lenses. What is the power in diopters of the combination is

A convex lens and a concave lens, each havaing same focal length of 25 cm, are put in contact to from a combination of lenses. The power of the combination (in diopter) is

A convex lens and a concave lens ,each having same focal length of 25 cm,are put in contact to form a combination of lenses.the power of the combination (in diopters) is

A convex lens of focal length 40 cm a concave lens of focal length 40 and a concave lens of focal length 15 cm are placed in contact. The power of this combination of are placed in contact. The power of this combination in diopters is

A convex lens of Focal length of 40cm is in contact with a concave lens of focal length 25cm. The power of the combination is.

A convex lens of focal length 40 cm is in contact with a concave lens of focal length 25 cm. The power of the combination is

A convex lens of focal length 40 cm is in contact with a concave lens of focal length 25 cm. The power of the combination is

A convex lens of focal lenth 30 cm and a concave lens of focal length 60 cm are placed in contact.Find the power of the combination.