← Back to lesson·Advance A · W5 D2 · 1 drill section · ~5 min

Advance A · Week 5 · Advanced Paper-and-Mental Techniques

Day 2 Practice Worksheet — Cross-Multiplication Method (2×2)

(ab)(cd) = ac · 100 + (ad + bc) · 10 + bd.

Name
Date
Score

  1. §12-digit × 2-digit

    ⏱ 5 min · 20 problems

    Timed drill — start a 5-minute timer, then solve in order. Goal: finish under time with full accuracy.

    1. 01.52 × 84=
    2. 02.52 × 13=
    3. 03.96 × 69=
    4. 04.78 × 51=
    5. 05.86 × 19=
    6. 06.96 × 12=
    7. 07.63 × 82=
    8. 08.81 × 92=
    9. 09.83 × 50=
    10. 10.96 × 43=
    11. 11.41 × 39=
    12. 12.45 × 75=
    13. 13.77 × 70=
    14. 14.87 × 31=
    15. 15.97 × 85=
    16. 16.47 × 27=
    17. 17.28 × 14=
    18. 18.26 × 92=
    19. 19.14 × 70=
    20. 20.45 × 38=

Answer Key

§1 · 2-digit × 2-digit

  1. 1.4368
  2. 2.676
  3. 3.6624
  4. 4.3978
  5. 5.1634
  6. 6.1152
  7. 7.5166
  8. 8.7452
  9. 9.4150
  10. 10.4128
  11. 11.1599
  12. 12.3375
  13. 13.5390
  14. 14.2697
  15. 15.8245
  16. 16.1269
  17. 17.392
  18. 18.2392
  19. 19.980
  20. 20.1710