Finding the Third Proportional to 420 and 518
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Solution
The third proportional to 420 and 518 is: 638.87
Step by Step Solution
- Step 1: Write the proportion equation
420 : 518 = 518 : x - Step 2: Convert to fraction form
420/518 = 518/x - Step 3: Cross multiply
420x = 518 × 518 - Step 4: Simplify right side
420x = 268,324 - Step 5: Solve for x
x = 268,324/420 - Step 6: Final answer
x = 638.87
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These problems maintain the same ratio (1.23) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.