Question

Row 159.26 463.54 49.3 60.6 82.4 90.9 612.56 720.15 424.35 979.52 99.6

Answer 1

1.

$X_{3,3}=Element \;in\;third\;row\;and\;third\;column=56.9$

2.

$\sum_{i=3}^{10}X_{i,2}=Sum\;of\;elements\;of\;second\;column\;from\;third\;row\;to\;tenth\;row$

$\!\!\!\! \!\!\!\!\!\!=575.85+567.66+567.81+616.68+720.15+782.62+728.84+979.52=5539.13$

3.

$\sum_{j=2}^{3}X_{3,j}=Sum\;of\;elements\;of\;third\;row\;from\;second\;column\;to\;third\;column$

$=575.85+56.9=632.75$

4.

$\sum_{i=2}^{7}\sum_{j=1}^{3}X_{i,j}=Sum\;of\;all\;elements\;from\;second\;row\;to\;seventh\;row$

$\!\!\!\!\!\!\!\!\!\!\!\!\!\!\!\!=161.02+124.84+147.71+193.22+306.68+612.56+483.55+575.85+567.66+567.81+616.68+720.15+53.8+56.9+60.6+65.2+72.6+82.4$

$=5469.23$