If 200 ml of water was poured onto a soil sample in a beaker and 25% of the water drained through the soil, it means that 75% of the water remains retained in the soil.

To find the amount of water retained in the soil, we can calculate 75% of the original 200 ml of water:

Amount of water retained = 0.75 (75%) * 200 ml = 150 ml

So, 150 ml of water is retained in the soil after 25% of the water has drained through.