Home / 417.29-626.03-128.72

Finding the Fourth Proportional to 417.29, 626.03 and 128.72

Calculator

Solution

The fourth proportional to 417.29, 626.03 and 128.72 is: 193.11

Step by Step Solution

  1. Step 1: Write the proportion equation
    417.29 : 626.03 = 128.72 : x
  2. Step 2: Convert to fraction form
    417.29/626.03 = 128.72/x
  3. Step 3: Cross multiply
    417.29x = 626.03 × 128.72
  4. Step 4: Simplify right side
    417.29x = 80,582.58
  5. Step 5: Solve for x
    x = 80,582.58/417.29
  6. Step 6: Final answer
    x = 193.11

Related Problems

Find fourth proportional to 208.65, 313.02 and 64.36
Half scale
Find fourth proportional to 834.58, 1,252.06 and 257.44
Double scale
Find fourth proportional to 418.29, 627.53 and 129.72
Similar ratio
Find fourth proportional to 625.94, 939.05 and 193.08
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.