Rick's savings are half the price of the gift, which is $250/2 = $<<250/2=125>>125.
The total savings for the two siblings is $155 + $125 = $<<155+125=280>>280.
Mom's gift costs $250 + $25 for the cake = $<<250+25=275>>275
Subtracting the total cost of the gift from the total savings, we get $280 - $275 = $<<280-275=5>>5 left.
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