A. On April 28, 2015, the Plaintiff, a manufacturer of ready-mixed, entered into a contract for the supply of ready-mixed (hereinafter “instant contract”) with Defendant A Co., Ltd. (hereinafter “Co., Ltd.”) on the packing site of the Da factory at the time of the Jin-si (hereinafter “instant construction work” and its site “the construction site at the instant construction site”) with the Defendant A Co., Ltd. (hereinafter “Co., Ltd.”). The Plaintiff, a manufacturer of ready-mixed, supplied ready-mixed at the 60,000 won per cubic meter (excluding value-added tax) and the price to be paid within 20 days from the date of the claim.

On the same day, Defendant B and Defendant C jointly guaranteed the obligation to be borne by Defendant A to the Plaintiff under the instant contract.

B. On May 2, 2015, the Plaintiff supplied the instant construction site amounting to KRW 95,304,00,000 in total from 1,04 cubic meters and 400 cubic meters of ready-mixed on May 14, 2015 (=86,640,000 cubic meters = = 1,444 cubic meters (=400 cubic meters) ¡¿ 60,000 cubic meters) x 60,000 cubic meters).

C. On May 4, 2015, Defendant A paid KRW 7,000,000 to the Plaintiff out of the amount of ready-mixed.

On June 30, 2015, the Plaintiff issued an electronic tax invoice to Defendant A and filed a claim for the payment of unpaid ready-mixed price.

[Ground of recognition] Facts without dispute, Gap evidence Nos. 4, 5, 6, 7 and the purport of the whole pleadings

2. According to the facts of the determination as to the cause of the claim, the Defendants are jointly and severally liable to pay the Plaintiff the amount of KRW 88,304,00 (i.e., KRW 95,304,00- KRW 7,000) and damages for delay at the rate of 15% per annum as prescribed by the Act on Special Cases Concerning the Promotion, etc. of Legal Proceedings, from July 21, 2015, the day following the lapse of 20 days from June 30, 2015, for which the Plaintiff requested payment, until April 15, 2016, a duplicate of the application for change of the purport of the claim and the cause of the claim, delivered to the Defendant B and C, until April 14, 2016, and from the following day until the date of full payment.

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