Finding the Fourth Proportional to 780.68, 1,077 and 470
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Solution
The fourth proportional to 780.68, 1,077 and 470 is: 648.40
Step by Step Solution
- Step 1: Write the proportion equation
780.68 : 1,077 = 470 : x - Step 2: Convert to fraction form
780.68/1,077 = 470/x - Step 3: Cross multiply
780.68x = 1,077 × 470 - Step 4: Simplify right side
780.68x = 506,190 - Step 5: Solve for x
x = 506,190/780.68 - Step 6: Final answer
x = 648.40
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Why These Related Problems?
These problems maintain the same ratio (1.38) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.