Solve: 1599 ÷ 39.99 + (4/5) × 2449 − 120.05 = ?

Concept

Simplification (BODMAS) problems that mix a decimal division, a fraction of a large number, and a decimal subtraction are solved fastest by first rounding every term to the nearest convenient value that keeps the expression numerically close to the original, and then applying division and multiplication before addition and subtraction, strictly left to right.

Application

1. Round each term to a convenient nearby value: 1599 → 1600, 39.99 → 40, 2449 → 2450, and 120.05 → 120.

2. Rewrite the expression with the rounded values: 1600 ÷ 40 + (4/5) × 2450 − 120.

3. Carry out the division first: 1600 ÷ 40 = 40.

4. Carry out the multiplication next: (4/5) × 2450 = 1960.

5. Add the two results: 40 + 1960 = 2000.

6. Subtract the last term: 2000 − 120 = 1880.

Cross-check

Evaluating the original expression exactly (without rounding) gives 1599 ÷ 39.99 + (4/5) × 2449 − 120.05 ≈ 1879.13, which is within a few units of the rounded result — confirming the rounding approximation above is valid and the two values agree to the nearest option offered.