Home / 379.74-569.78-257.72

Finding the Fourth Proportional to 379.74, 569.78 and 257.72

Calculator

Solution

The fourth proportional to 379.74, 569.78 and 257.72 is: 386.70

Step by Step Solution

  1. Step 1: Write the proportion equation
    379.74 : 569.78 = 257.72 : x
  2. Step 2: Convert to fraction form
    379.74/569.78 = 257.72/x
  3. Step 3: Cross multiply
    379.74x = 569.78 × 257.72
  4. Step 4: Simplify right side
    379.74x = 146,843.70
  5. Step 5: Solve for x
    x = 146,843.70/379.74
  6. Step 6: Final answer
    x = 386.70

Related Problems

Find fourth proportional to 189.87, 284.89 and 128.86
Half scale
Find fourth proportional to 759.48, 1,139.56 and 515.44
Double scale
Find fourth proportional to 380.74, 571.28 and 258.72
Similar ratio
Find fourth proportional to 569.61, 854.67 and 386.58
1.5x scale

Why These Related Problems?

These problems maintain the same ratio (1.50) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.