There are 156, 208 and 260 students in
groups a, b, c respectively. buses are to be hired to take them for a field
trip. find the minimum number of buses to be hired if the same number of
students should be accommodate in each bus.

How do i do this? i don’t understand

Dexter read 11 science fiction books and 5 history books. lena read 9 science fiction books and 4 history books. compare the students’ ratios of science fiction books to history books. 1. determine the ratios’ form:    science fiction books to history books 2. write the ratios as fractions:    dexter: 115; lena: 94 3. rewrite with a common denominator. 4. compare. 5. answer the question. determine which shows the correct comparison of the ratios for this problem.

In need of in the diagram, ∠abc is a right angle. ∠dbc = 30°27'40". find the measure of ∠abd.