Finding the Third Proportional to 418 and 640
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Solution
The third proportional to 418 and 640 is: 979.90
Step by Step Solution
- Step 1: Write the proportion equation
418 : 640 = 640 : x - Step 2: Convert to fraction form
418/640 = 640/x - Step 3: Cross multiply
418x = 640 × 640 - Step 4: Simplify right side
418x = 409,600 - Step 5: Solve for x
x = 409,600/418 - Step 6: Final answer
x = 979.90
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These problems maintain the same ratio (1.53) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.