Solution: suppose there are x dumplings left at the end, x

Before eating for the fourth time: 4x/3+ 1

Before eating the third time: (4x/3+1) * 4/3+1= (4/3) 2 * x+4/3+1.

Before eating for the second time: [(4/3) 2 * x+4/3+1] * 4/3+1= (4/3) 3 * x+(4/3) 2+4/3+1.

Original text: t = (4/3) 4 * x+(4/3) 3+(4/3) 2+4/3+1

=(256x+525)/8 1

=3x+6+ 13(x+3)/8 1

Suppose (x+3)/8 1=k, and k is an integer.

Because: 0

So: 0

0 & ltk & lt97/8 1

Then k= 1, x=78, t=256k-3=253.

So Pig Bajie got back 253 dumplings.