Numeric Entry & Multiple-Answer • Topic 4 of 4

On-Screen Calculator & Estimation

The GRE supplies an on-screen basic calculator — four operations, a square root, a percent key and a memory, and nothing more. It has no exponent, sine, or graphing functions, so it will not rescue a badly set-up problem; it only speeds up arithmetic you have already reasoned out. The strategic skill is knowing when NOT to use it. For Quantitative Comparison and for multiple choice with widely spaced answers, estimation is faster and less error-prone: round to friendly numbers and see which choice you land near. Reserve the calculator for messy exact arithmetic, especially on Numeric Entry where there are no choices to check against. Two cautions: transcribe carefully, since a mistyped digit produces a confidently wrong answer with no options to flag it, and mind the calculator’s display limits and order of operations — it will not respect implied grouping, so compute a bracketed expression in the right sequence yourself. Estimate first to know roughly what the answer should be, then let the calculator confirm the precise figure only when precision is actually required.

✅ Solved examples

1. Multiple choice with choices 18, 20, 24, 30. Estimate 19% of 106 to pick the answer.
Round: 19% ≈ 20% and 106 ≈ 100, so ≈ 20% of 100 = 20. The nearest choice is 20 — no calculator needed. (Exact is 20.14.)
2. Numeric Entry. Enter √784.
This is where the calculator earns its keep. Using the square-root key, √784 = 28 (since 28² = 784). Enter 28.
3. Quantitative Comparison. Quantity A: 48% of 250. Quantity B: 130. Estimate to answer.
48% ≈ 50%, and 50% of 250 = 125, which is below 130 — but 48% is a touch under 50%, so Quantity A is even smaller, about 120. So Quantity A < 130: Quantity B is greater. Estimation settles it without exact multiplication.
4. Numeric Entry. A store sells 1,240 items at $37 each. Enter the total revenue in dollars.
Estimate first: 1,240 × 37 ≈ 1,200 × 37 ≈ 44,400, so the answer is around $46,000. Now use the calculator for the exact figure: 1,240 × 37 = 45,880. Enter 45880. (The estimate confirms you did not mistype.)

✏️ Practice — try these, take hints as needed

1. Choices 40, 45, 50, 60. Estimate 51% of 98.
Round 51% to 50% and 98 to 100.
50% of 100 = 50.
Pick the nearest choice.
50
2. Numeric Entry. Enter √576.
Use the square-root key.
24² = 576.
Enter the root.
24
3. QC estimate. Quantity A: 32% of 400. Quantity B: 120. Which is greater?
32% ≈ 1/3.
1/3 of 400 ≈ 133.
Compare to 120.
A (128 > 120)
4. Numeric Entry. 2,050 × 48 — estimate first, then give the exact product.
≈ 2,000 × 48 = 96,000.
Compute exactly with the calculator.
2,050 × 48.
98,400
5. Choices 6, 8, 12, 15. Estimate 24.6 ÷ 3.1.
Round to 24 ÷ 3.
= 8.
Nearest choice.
8

📝 Topic test — 8 questions

Auto-graded with full solutions; saved to your dashboard. Use the calculator and formula sheet (top-right) any time.

Loading questions…
← Checking Every Option Take the chapter test →