The first picture has 2 rows and 3 columns, and a * * * has 2×3=6 (pieces);

The second picture has 3 rows and 4 columns, and a * * * has 3×4= 12 (pieces);

The third picture has 4 rows and 5 columns, a * * * 4×5 = 20 (pieces);

You can get the law:

The nth graph has (n+ 1) rows and (n+2) columns, and a * * * has (n+ 1)(n+2).

When n=99, a * * * has100×10/=1kloc-0/00 (pieces).

Look at the picture to find the law, so that the law can be expressed by a formula containing n, and then substitute the number into the formula to find the result.

Extended data:

3×5 means the addition of five 3s.

5x3 represents the addition of three 5s.

Ⅰ? Multiplication principle: If the dependent variable f is in direct proportion to the independent variable X 1, X2, X3...Xn, and each independent variable is qualitatively different, if any independent variable f is missing, it will lose its meaning, which is called multiplication.

In probability theory, the result of an event needs to be divided into n steps, the first step 1 includes M 1 different results, the second step includes M2 different results, …, and the n step includes Mn different results. Then this event may have n = m 1× m2× m3×…× Mn different results.

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