Students with low academic language proficiency are often considered to meet specific comprehension challenges with word problems. But how do conceptual and reading challenges interfere in these situations? We approach this question by investigating how performance depends on the problem format for different problem types. A test with N=250 students investigates cracking percent problems in pure, text, and visual format. The results show that text formats are most difficult for elementary problem types, whereas (context t can enhance the accessibility for more complex problem types. Item difficulties differ similarly for students with high and low language proficiency, hence reading challenges seem as crucial as conceptual challenges. A deeper analysis shows specific linguistic challenges with the expressions reduced to and reduced by.