Finding the Third Proportional to 421 and 690
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Solution
The third proportional to 421 and 690 is: 1,130.88
Step by Step Solution
- Step 1: Write the proportion equation
421 : 690 = 690 : x - Step 2: Convert to fraction form
421/690 = 690/x - Step 3: Cross multiply
421x = 690 × 690 - Step 4: Simplify right side
421x = 476,100 - Step 5: Solve for x
x = 476,100/421 - Step 6: Final answer
x = 1,130.88
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These problems maintain the same ratio (1.64) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.