Answer:
Given,
The number divides 315 (320 – 5) and 450 (457 – 7).
∴ Required number = HCF (315, 450)
Apply Euclid’s algorithm,
315 ) 450 ( 1
– 315
____________
135 ) 315 ( 2
– 270
____________
45 ) 135 ( 3
– 135
____________
0
HCF of 315 and 450 is 45.
The number is 45.