Difficulty: Medium
Correct Answer: 50
Explanation:
Introduction / Context:In point handicaps, “A gives B 15” in an N-point game means when A scores N, B would score N − 15 in the same time, implying a speed ratio. Consistency across three pairwise handicaps pins down N.
Given Data / Assumptions:
Concept / Approach:Ratios must satisfy (vA/vB) * (vB/vC) = vA/vC. Substitute the expressions and solve for N.
Step-by-Step Solution:
(N/(N − 15)) * (N/(N − 10)) = N/(N − 22)Cancel one N: N/(N − 15) * 1/(N − 10) = 1/(N − 22)Cross-multiply: (N − 22) * N = (N − 15)(N − 10)Expand: N^2 − 22N = N^2 − 25N + 150 ⇒ 3N = 150 ⇒ N = 50Verification / Alternative check:Plug N = 50 back to get ratios 50/35, 50/28, and 50/40; they satisfy the identity.
Why Other Options Are Wrong:60/70/80 do not satisfy the consistency equation for all three pairwise handicaps.
Common Pitfalls:Adding or averaging handicaps; correct method uses multiplicative speed ratios.
Final Answer:50
Discussion & Comments