An oblong number is the number of dots in a rectangular grid with one more row than column. The first four oblong numbers are 2, 6, 12, and 20, and are represented below:

![](https://cdn.mathpix.com/cropped/2024_04_20_ac36362783317e0251fdg-044.jpg?height=366&width=919&top_left_y=1205&top_left_x=560)

What is the 7th oblong number?
(A) 42
(B) 49
(C) 56
(D) 64
(E) 72
The 7th oblong number is the number of dots in retangular grid of dots with 7 columns and 8 rows.

Thus, the 7 th oblong number is $7 \times 8=56$.

ANSWER: (C)