Question

$61 \times 14 \times {127}^{18}$ എന്നതിൻ്റെ ഗുണനഫലത്തിലെ യൂണിറ്റ് ഡിജിറ്റ് കണ്ടെത്തുക

• A. 1
• B. 8
• C. 2
• D. 6

Answer 1

Answer:

D. 6

$61 \times 14 \times {127}^{18}$

To find the unit digit, focus only on the last digit of each number.

• Step 1: First Part
  Multiply the last digits of $61$ and $14$:
  $1 \times 4 = 4$

• Step 2: Second Part (${127}^{18}$)

  • Take the last digit of the base, which is $7$.

  • Divide the power ($18$) by $4$ to find the remainder:
    $18 \div 4 = 4 \text{ with a remainder of } 2$

  • Raise the base digit to this remainder:
    $7^2 = 49$

  • The unit digit for this part is $9$.

• Step 3: Final Multiplication
  Multiply the unit digits from Step 1 and Step 2:
  $4 \times 9 = 36$

Final Answer:
The unit digit is 6.