Question 20
A square is formed from 243 rectangles measuring 1 cm by 3 cm. Find the difference between the total perimeters before and after joining, in cm.
Source glossary (English–Vietnamese): Square: hình vuông; Rectangle: hình chữ nhật; Difference: hiệu; Total perimeter: tổng chu vi.
Source glossary (English–Vietnamese): Square: hình vuông; Rectangle: hình chữ nhật; Difference: hiệu; Total perimeter: tổng chu vi.