Bruce filled his koi tank with 1040 $$l$$ of water. <br>Over the week, 120 $$l$$ of water was lost. <br>He then piped in another 150 $$l$$ of water.<hr>At the end, there was <input min="0" type="number" id ="imp2pg224q9_1" class="lineinput" placeholder="?" /> $$l$$ of water in the tank.