can someone help me understand using vector addition how I can add the first term of three terms and keep going? here's and example if I didn't explain that too well.

X1 X2 X3......X100

+Y1 +Y2...................

+Z1 +Z2...................

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R1 R2.........................

and it can be less than 100, 100 is a variable but it is the highest the variable can go