Updated with further terms of the ConAgra/Ralcorp merger agreement

NEW YORK (

TheStreet

) --

ConAgra Foods

(CAG) - Get Report

said Tuesday it agreed to buy

Ralcorp Holdings

(RAH)

for $90 a share in cash, or about $5 billion.

The purchase price is a 28.2% premium to Ralcorp's closing price Monday of $70.23.

Ralcorp shares were soaring in premarket trading Tuesday, up 26.7% to $88.99.

The total value of the deal, including assumed debt, is $6.8 billion.

A combined ConAgra/Ralcorp will have annual sales of about $18 billion, the companies said in a statement Tuesday.

-- Written by Joseph Woelfel

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Joseph Woelfel

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