Finding the Third Proportional to 420 and 978.75
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Solution
The third proportional to 420 and 978.75 is: 2,280.84
Step by Step Solution
- Step 1: Write the proportion equation
420 : 978.75 = 978.75 : x - Step 2: Convert to fraction form
420/978.75 = 978.75/x - Step 3: Cross multiply
420x = 978.75 × 978.75 - Step 4: Simplify right side
420x = 957,951.56 - Step 5: Solve for x
x = 957,951.56/420 - Step 6: Final answer
x = 2,280.84
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Why These Related Problems?
These problems maintain the same ratio (2.33) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.