Answer:
option D
Step-by-step explanation:
[tex]20r + 60t\\\\= (4 \times 5 \times r) + (4 \times 5 \times 3 \times t) \ \ \ \ \ [ 20 = 4 \times 5, \ 60 = 4 \times 5 \times 3] \\ \\=(20 \times r ) + ( 20\times 3 \times t)\\\\=20 \times r + 20 \times 3t\\\\= 20 \times ( r + 3t)\\\\=20( r + 3t)[/tex]
