Finding the Third Proportional to 274 and 420
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Solution
The third proportional to 274 and 420 is: 643.80
Step by Step Solution
- Step 1: Write the proportion equation
274 : 420 = 420 : x - Step 2: Convert to fraction form
274/420 = 420/x - Step 3: Cross multiply
274x = 420 × 420 - Step 4: Simplify right side
274x = 176,400 - Step 5: Solve for x
x = 176,400/274 - Step 6: Final answer
x = 643.80
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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.