ꯑꯣꯏꯒꯅꯤ꯫ ꯕꯤꯁꯥꯅꯅꯥ ꯂꯦꯞꯄꯥ ꯂꯩꯇꯅꯥ ꯈꯣꯡꯖꯦꯜ ꯌꯥꯡꯅꯥ 120 km ꯁꯥꯏꯀꯜ ꯊꯧꯈꯤ꯫ ꯃꯍꯥꯛꯅꯥ 3 km/hr ꯍꯦꯟꯅꯥ ꯇꯞꯅꯥ ꯁꯥꯏꯀꯜ ꯊꯧꯔꯝꯂꯕꯗꯤ ꯃꯍꯥꯛꯅꯥ ꯃꯐꯝ ꯑꯗꯨꯗꯥ ꯌꯧꯕꯗꯥ ꯄꯨꯡ 2 ꯍꯦꯟꯅꯥ ꯆꯪꯂꯃꯒꯅꯤ꯫ ꯃꯍꯥꯛꯀꯤ ꯇꯁꯦꯡꯕꯥ ꯈꯣꯡꯖꯦꯜ ꯑꯗꯨ ꯀꯤꯂꯣꯃꯤꯇꯔ/ꯄꯨꯡꯗꯥ ꯈꯪꯗꯣꯀꯎ꯫

ꯑꯣꯏꯒꯅꯤ꯫ 1 ꯍꯥꯌꯅꯥ ꯀꯧꯏ꯫ ꯇꯁꯦꯡꯕꯥ ꯈꯣꯡꯖꯦꯜ ꯑꯁꯤ v ꯑꯣꯏꯔꯁꯅꯨ, ꯃꯗꯨꯒꯤ ꯃꯇꯨꯡꯗꯥ 120/(v−3) − 120/v = 2꯫ 2 ꯍꯥꯌꯅꯥ ꯀꯧꯏ꯫ ꯇꯦꯁ꯭ꯠ ꯇꯧꯕꯥ v = 15: 120/12 − 120/15 = 10 − 8 = 2꯫ 3 ꯍꯥꯌꯅꯥ ꯀꯧꯏ꯫ ꯀꯟꯗꯤꯁꯟ ꯑꯁꯤ ꯁꯣꯌꯗꯅꯥ ꯂꯩ, ꯃꯔꯝ ꯑꯗꯨꯅꯥ ꯇꯁꯦꯡꯕꯥ ꯈꯣꯡꯖꯦꯜ = 15 km/hr. _ꯁꯣꯔꯁ: ꯑꯥꯔ.ꯑꯥꯔ.ꯕꯤ.ꯒꯤ ꯒ꯭ꯔꯨꯞ D ꯁꯤ.ꯏ.ꯑꯦꯟ.-02/2018 ꯄꯤ.ꯋꯥꯏ.ꯀ꯭ꯌꯨ., Q.78._