* * *
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In this cryptarithm both the digits and operations have been removed. Each digit is a prime (2, 3, 5, or 7). Give the correct arrangement of digits and the two operations.
I assumed that the operation was multiplication, as that is what the layout looks like, and that, while the digits are represented by asterisks, the operator for multiplication was merely left out, as, if the multiplication were by a single digit there would be no second line of partial product.
Further, though addition is involved, the absence of a sign for addition is not unusual for this type of problem. It hasn't really been removed, rather it is never really present.
This does work out as a unique multiplication algorithm presentation:
775
33
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2325
2325
-----
25575
found by:
clearvars
t='2357';
for a1=[2 3 5 7]
for a2=[2 3 5 7]
for a3=[2 3 5 7]
a=100*a1+10*a2+a3;
for b1=[2 3 5 7]
for b2=[2 3 5 7]
b=10*b1+b2;
p1=b2*a;
p2=b1*a;
p=a*b;
tst=[num2str(p1) num2str(p2) num2str(p)];
v=ismember(tst,t);
if v
disp(a)
disp(b)
disp(p1)
disp(p2)
disp(p)
end
end
end
end
end
end
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Posted by Charlie
on 2025-02-19 09:07:42 |
computer solution
