Home / 93.84-139.92-87

Finding the Fourth Proportional to 93.84, 139.92 and 87

Calculator

Solution

The fourth proportional to 93.84, 139.92 and 87 is: 129.72

Step by Step Solution

  1. Step 1: Write the proportion equation
    93.84 : 139.92 = 87 : x
  2. Step 2: Convert to fraction form
    93.84/139.92 = 87/x
  3. Step 3: Cross multiply
    93.84x = 139.92 × 87
  4. Step 4: Simplify right side
    93.84x = 12,173.04
  5. Step 5: Solve for x
    x = 12,173.04/93.84
  6. Step 6: Final answer
    x = 129.72

Related Problems

Find fourth proportional to 46.92, 69.96 and 43.50
Half scale
Find fourth proportional to 187.68, 279.84 and 174
Double scale
Find fourth proportional to 94.84, 141.41 and 88
Similar ratio
Find fourth proportional to 140.76, 209.88 and 130.50
1.5x scale

Why These Related Problems?

These problems maintain the same ratio (1.49) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.