Finding the Third Proportional to 257 and 690.50
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Solution
The third proportional to 257 and 690.50 is: 1,855.21
Step by Step Solution
- Step 1: Write the proportion equation
257 : 690.50 = 690.50 : x - Step 2: Convert to fraction form
257/690.50 = 690.50/x - Step 3: Cross multiply
257x = 690.50 × 690.50 - Step 4: Simplify right side
257x = 476,790.25 - Step 5: Solve for x
x = 476,790.25/257 - Step 6: Final answer
x = 1,855.21
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Why These Related Problems?
These problems maintain the same ratio (2.69) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.