The true number sentence is the third option:
6.8*1.3 = 8.84
Here we have number sentences of the form:
A*B = C
This is true only when the value of the product A*B is equal to the value of C.
One key thing to identify the correct one is remembering the rule of signs:
(+)*(-) = (-)
(+)*(+) = (+)
(-)*(+) = (-)
(-)*(-) = (+).
The only option that meets that rule is:
6.8*1.3 = 8.84
Where the product of two positive numbers gives another positive number (and the equality is true) so we conclude that this number sentence is true.
If you want to learn more about number sentences:
https://brainly.com/question/2972832
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