プログレッシブ和英中辞典(第4版)の解説
ごぶごぶ【五分五分】
五分五分の fifty-fifty; even
五分五分に分けましょう
Let's go fifty-fifty.
双方五分五分の実力［力量］である
They are 「equally good [evenly matched].
彼らが成功する可能性は五分五分だ
There's a fifty-fifty chance that they'll succeed.／They have 「a fifty-fifty [an even] chance of succeeding.