Question

Find the largest number that will divide 623, 729 and 841 leaving a remainder of 3, 9 and 1 respectively.

• A. 80
• B. 60
• C. 40
• D. 20

Answer 1

The correct option is D

20

The numbers 623, 729 and 841 leave a remainder of 3, 9 and 1 respectively.

$\therefore$ Number will be 623 - 3 = 620

729 - 9 = 720

841 - 1 = 840

Find the HCF of 620, 720 and 840.

Find the H.C.F of 620 and 720.

20 is the HCF of 620 and 720.

Find the HCF of 20 and 840.

H.C.F of 20 and 840 is 20

$\therefore$ H..CF of 620, 720 and 840 is 20.

$\therefore$ The required largest number that will divide 623, 729 and 841 leaving a remainder of 3, 9 and 1 respectively = 20.