Anita's mathematics test had 70 problems carrying equal marks i.e., 10 arithmetic, 30 algebra and 30 geometry. Although she answered 70% of the arithmetic, 40% of the algebra and 60% of the geometry problems correctly, she did not pass the test because she got less than 60% marks. The number of more questions she would have to answer correctly to earn a 60% passing marks is :

Correct Option: (b) 5

Anita's test has 70 problems carrying equal marks, consisting of 10 arithmetic, 30 algebra, and 30 geometry problems. She correctly answered: Arithmetic: 70% of 10 = 7 problems. Algebra: 40% of 30 = 12 problems. Geometry: 60% of 30 = 18 problems. Total questions she answered correctly = 7 + 12 + 18 = 37 problems. To pass the test, she needs to score at least 60% marks. Since all questions carry equal marks, she must answer at least 60% of the total questions correctly. Required correct questions to pass = 60% of 70 = 42 problems. The number of additional questions she needs to answer correctly is 42 - 37 = 5 problems. Therefore, option (b) is correct.