Question

Problem 3
Anh, Bill and Cathy each think of a positive whole number less than 1000.
• Anh says, My number is bigger than 500 and divides by every integer
from 1 to 10 except for 7.'
• Bill says, "My number divides by every integer from 1 to 10 except
for 9.
• Cathy says, 'You have both done better than me, but I can see that
if we added our three numbers together, the total would divide by
all the numbers from 1 to 10.'
What numbers from 1 to 10 does Cathy's number not divide by?

Answer 1

Answer:

Cathy's number is not divide by 7 and 9

Step-by-step explanation:

Anh’s number is divisible by all numbers from 1 to 10 except 7.  

Hence, Anh’s number is 8*9*10 = 720

Bill’s number  does not divide by 9, hence his number would be = 3*8*5*7 = 840

The sum of numbers of all three is divisible by all numbers between 1 to10  

So the sum number is = 10*9*8*7 = 5040

Number of Cathy = 2520  – 720 -840 = 960

960 is not divisible by 7 and 9