Home / 266.07-398.57-128.71

Finding the Fourth Proportional to 266.07, 398.57 and 128.71

Calculator

Solution

The fourth proportional to 266.07, 398.57 and 128.71 is: 192.81

Step by Step Solution

  1. Step 1: Write the proportion equation
    266.07 : 398.57 = 128.71 : x
  2. Step 2: Convert to fraction form
    266.07/398.57 = 128.71/x
  3. Step 3: Cross multiply
    266.07x = 398.57 × 128.71
  4. Step 4: Simplify right side
    266.07x = 51,299.94
  5. Step 5: Solve for x
    x = 51,299.94/266.07
  6. Step 6: Final answer
    x = 192.81

Related Problems

Find fourth proportional to 133.04, 199.29 and 64.36
Half scale
Find fourth proportional to 532.14, 797.14 and 257.42
Double scale
Find fourth proportional to 267.07, 400.07 and 129.71
Similar ratio
Find fourth proportional to 399.11, 597.86 and 193.07
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.