Home / 1,515-2,272.50-489

Finding the Fourth Proportional to 1,515, 2,272.50 and 489

Calculator

Solution

The fourth proportional to 1,515, 2,272.50 and 489 is: 733.50

Step by Step Solution

  1. Step 1: Write the proportion equation
    1,515 : 2,272.50 = 489 : x
  2. Step 2: Convert to fraction form
    1,515/2,272.50 = 489/x
  3. Step 3: Cross multiply
    1,515x = 2,272.50 × 489
  4. Step 4: Simplify right side
    1,515x = 1,111,252.50
  5. Step 5: Solve for x
    x = 1,111,252.50/1,515
  6. Step 6: Final answer
    x = 733.50

Related Problems

Find fourth proportional to 757.50, 1,136.25 and 244.50
Half scale
Find fourth proportional to 3,030, 4,545 and 978
Double scale
Find fourth proportional to 1,516, 2,274 and 490
Similar ratio
Find fourth proportional to 2,272.50, 3,408.75 and 733.50
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.