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Algebra Difficulty 3.1 AMC 10/12 Find the answer

Given that aa, bb, and cc are three consecutive positive integers, and a2=97344a^2=97344, c2=98596c^2=98596. Find the value of bb.

A number or a short expression. Spacing and $ signs are ignored.

Solution

Analysis: Since a2=97344a^2=97344 and c2=98596c^2=98596, by using the difference of squares formula, we get (c+a)(ca)=1252(c+a)(c-a)=1252. Given that aa, bb, and cc are three consecutive positive integers, we have ca=2c-a=2 (1). Therefore, we can calculate c+a=626c+a=626 (2). From (1) and (2), we can solve for cc, and thus find the value of bb.

Let's solve it step by step:

1. From the given, we know a2=97344a^2=97344 and c2=98596c^2=98596. Using the difference of squares, we have:
(c+a)(ca)=c2a2=9859697344=1252 (c+a)(c-a)=c^2-a^2=98596-97344=1252

2. Since aa, bb, and cc are consecutive integers, we have:
ca=2(1) c-a=2 \quad \text{(1)}

3. From the equation above, we can find:
c+a=626(2) c+a=626 \quad \text{(2)}

4. Solving equations (1) and (2) simultaneously, we can find the values of cc and aa, and thus determine bb as the integer between aa and cc.

Therefore, the value of bb is 313\boxed{313}.

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Source: NuminaMath-1.5, licensed Apache-2.0. Statement and solution reproduced as published; topic and difficulty added by this site.