Identify the correct mathematical statements: Choose the correct answer from the options given below:

1.The expression 1/(5x6) + 1/(6x7) + 1/(7x8) + ... + 1/(24x25) is equal to 4/25.

2.Of the three numbers, second is twice the first and is also thrice of the third. If the average of three numbers is 55, then largest number is 90.

3.If (a+b):(b+c):(c+a) = 6:7:8 and a+b+c = 14, then value of c is 8.

4.2x0.2 + 0.02x0.02 - 0.4x0.02) / 0.18 is equal to 0.09.

A1, 2 & 4 only

B2 & 3 only

C2 & 4 only

D1 & 2 only ✓ Correct

Correct answer: (D) 1 & 2 only

Explanation

Statements 1 and 2 are correct.

Statement 1: the telescoping sum = 1/5 - 1/25 = 4/25.

Statement 2: 11a/3 = 165 gives a = 45, largest = 2a = 90.

Statement 3: a+b = 8 so c = 14 - 8 = 6, not 8.

Statement 4: (0.18)^2 / 0.18 = 0.18, not 0.09.

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