All pairs

Determine all pairs (m, n) of natural numbers for which is true:
m s (n) = n s (m) = 70,
where s (a) denotes the digit sum of the natural number a.

Correct answer:

d1 =  70

Step-by-step explanation:

m1=56;n1=59 m2=57;n2=58 m3=60;n3=64 m4=61;n4=63 m5=62;n5=62  d1=m1+5+9=56+5+9=70

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