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DSSSB PGT English Female General Section - 30 June 2021 Shift 2

Option 4 : 11 : 17

**Given:**

2x = 4y = 7z

**Concept:**

if a : b : c then,

a = b = c = K, where K is a constant

**Calculation:**

Let be assume K is equal to 2x = 4y = 7z then,

⇒ 2x = 4y = 7z = K

⇒ x = K/2 ----(1)

⇒ y = K/4 ----(2)

⇒ z = K/7 ----(3)

⇒ (x - y + z) : (x + y - z)

⇒ By equation (1), (2), and (3)

⇒ (K/2 - K/4 + K/7) : (K/2 + K/4 - K/7)

⇒ (14K - 7K + 4K)/28 : (14K + 7K - 4K)/28

⇒ 11K : 17K

⇒ 11 : 17

**∴ The required result will be 11 : 17.**