1. Basic facts

A. On October 1, 2014, the Plaintiff concluded a contract on October 1, 2014 (hereinafter “instant contract”) with the Defendant, under which the period for commencement of the instant construction works is KRW 780,000,000 (excluding value-added tax) on the date of completion of the completion of the construction works, on October 1, 2014, the date of commencement of the construction works, and on October 31, 2015, the total contract amount is KRW 780,000 (excluding value-added tax).

B. According to a written estimate attached to the instant contract agreement, “construction works: 340,440,000 won: 50,000,000 won for dismantling: volume: volume 153,093 cubic meters, volume 389,560,000 in total, and total amount 780,000,000 won.”

C. The Plaintiff, after installing the arrangement plant in accordance with the instant contract, produced concrete in accordance with the Defendant’s order, and the Defendant paid the construction cost under the instant contract to the Plaintiff as follows.

Serial 1 B/P installation costs 220,000 on January 21, 2015; 200, 2002: 20, 2000 on February 25, 2015; 374,000 on March 20, 2015; 6. 6. 6. 20. 8. 6. 16. 6. 2016. 8. 4. 6. 6. 205, 200 on March 20, 2005; 6. 8. 6. 6. 6. 205 on March 31, 2016, 200 on May 20, 2015;

D. By December 7, 2015, the Plaintiff produced concrete for the runway packing work.

【Ground for recognition】 The fact that there has been no dispute, Gap Nos. 1, 2, 6, 7, 12, 13 (including branch numbers; hereinafter the same shall apply), Eul's entries in the evidence Nos. 3 through 7, and 10, and the purport of the whole pleadings

2. The parties' arguments.