Fill in the blanks to find the product of 27 and 45.
27 × 45 = (20 +
) × (40 + 5)
= (20 ×
) + (20 × 5) + (7 × 40) + (7 × 5)
= 800 +
+ 280 + 35
So, the product of 27 and 45 is
.