In a mixture of alcohol and water the proportion of water by weight was 75%. If in the 120 gms mixture 30 gms water was added, what would be the percentage of water in the new mixture? शराब और पानी के मिश्रण में वजन के हिसाब से पानी का अनुपात 75% था। यदि 120 ग्राम मिश्रण में 30 ग्राम पानी मिलाया जाता है, तो नए मिश्रण में पानी का प्रतिशत कितना होगा?

Original mixture: 75% water means 90g water and 30g alcohol in 120g. After adding 30g water: total mixture = 150g, water = 90+30 = 120g. New % water = 120/150 × 100 = 80%. Wait, this is wrong. If water is 75% by weight, then in 120g: water = 0.75 × 120 = 90g, alcohol = 30g. Adding 30g water: water = 90+30 = 120g, total = 120+30 = 150g. % water = 120/150 = 0.8 = 80%. This matches the claimed answer.