this is test

In a class, 70 students wrote two tests wiz, test-I and test-II 50% of the students failed in test I and 40% of the students in test -II. How many students passed in both tests?

What is sure test of magnetism?

Why is Beilstein's test not regarded as a reliable test for the detection of a halogen in an organic compound?

Which of the following organic compounds answers to both iodoform test and Fehling's test?

Yellow precipitate obtained during the test halogen by lassaign's test is due to the formation of

Which substance is tested in case of toxicity/safety testing using transgenic animals?

A student's mean score on 5 tests was 84. The student's mean score on the first 4 of these tests was 87. What was the student's score on the fifth of these tests ?

In a series of tests, A appeared for 8 tests Each test was marked out of 30 and averages 25. However, while checking his files, A could only find 7 of the 8 tests. For these he scored 29 26, 18 ,20, 27, 24 and 29. Determine how many marks he scored for the eighth test.