Finding the Fourth Proportional to 79.50, 109.71 and 45
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Solution
The fourth proportional to 79.50, 109.71 and 45 is: 62.10
Step by Step Solution
- Step 1: Write the proportion equation
79.50 : 109.71 = 45 : x - Step 2: Convert to fraction form
79.50/109.71 = 45/x - Step 3: Cross multiply
79.50x = 109.71 × 45 - Step 4: Simplify right side
79.50x = 4,936.95 - Step 5: Solve for x
x = 4,936.95/79.50 - Step 6: Final answer
x = 62.10
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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.