Sanjay and Suresh together weigh 120 kg. Sanjay weighs 30 kg more than Suresh. What is the ratio of Suresh’s weight to Sanjay’s weight (expressed as a decimal)?

Introduction / Context:
This is a linear equation problem. We convert the statements into algebra, find individual weights, and then compute the requested ratio as a decimal.

Given Data / Assumptions:
Total weight = 120 kg; Sanjay = Suresh + 30 kg.

Concept / Approach:
Solve for Suresh and Sanjay directly, then compute Suresh/Sanjay as a decimal.

Step-by-Step Solution:
Let Suresh = s; Sanjay = s + 30. Sum: s + (s + 30) = 120 ⇒ 2s = 90 ⇒ s = 45. Sanjay = 45 + 30 = 75. Ratio (Suresh/Sanjay) = 45 / 75 = 3/5 = 0.6.

Verification / Alternative check:
Check totals: 45 + 75 = 120 and difference is 30, both conditions satisfied.

Why Other Options Are Wrong:
0.4, 0.3, 0.25, 0.5 are not equal to 45/75.

Common Pitfalls:
Using Sanjay/Suresh instead of Suresh/Sanjay, or miscomputing the decimal form.

Final Answer:
0.6