【Question 1】
$$
1+3+5+7+\cdots+197+199=
$$
$\qquad$

Translate the above text into English, please retain the original text's line breaks and format, and output the translation result directly.
【Analysis and Solution】
Calculation, arithmetic sequence.
(Method 1)
The number of terms is $(199-1) \div 2+1=100$;
$$
1+3+5+7+\cdots+197+199=(1+199) \times 100 \div 2=10000 \text{. }
$$
(Method 2)
From $1 \sim 200$ there are 200 positive integers, among which there are $200 \div 2=100$ odd numbers; the sum of the first $n$ positive odd numbers is $n^{2}$;
$$
1+3+5+7+\cdots+197+199=100^{2}=10000 \text{. }
$$