the upper bound for the length is
.
<u>Step-by-step explanation:</u>
Lower and Upper Bounds
- The lower bound is the smallest value that will round up to the approximate value.
- The upper bound is the smallest value that will round up to the next approximate value.
Ex:- a mass of 70 kg, rounded to the nearest 10 kg, The upper bound is 75 kg, because 75 kg is the smallest mass that would round up to 80kg.
Here , A length is measured as 21cm correct to 2 significant figures. We need to find what is the upper bound for the length . let's find out:
As discussed above , upper bound for any number will be the smallest value in decimals which will round up to next integer value . So , for 21 :
⇒ 
21.5 cm on rounding off will give 22 cm . So , the upper bound for the length is
.
your answer will be 2 hours and 10 minutes
mark brainliest
(30 points) The coordinates of the vertices of quadrilateral JKLM are J(−3, 2) , K(3, 5) , L(9, −1) , and M(2, −3) .
Which statement correctly describes whether quadrilateral JKLM is a rhombus?
Quadrilateral JKLM is not a rhombus because there is only one pair of opposite sides that are parallel.
In order to solve this, you have to set up a systems of linear equations.
Let's say that children = c and adults = a
30a + 12c = 19,080
a + c = 960
I'm going to show you how to solve this system of linear equations by substitution, the easiest way to solve in my opinion.
a + c = 960
- c - c
---------------------- ⇒ Step 1: Solve for either a or c in either equation.
a = 960 - c
20(960 - c)+ 12c = 19,080
19,200 - 20c + 12c = 19,080
19,200 - 8c = 19,080
- 19,200 - 19,200
---------------------------------- ⇒ Step 2: Substitute in the value you got for a or c
8c = -120 into the opposite equation.
------ ---------
8 8
c = -15
30a + 12(-15) = 19,080
30a - 180 = 19,080
+ 180 + 180
-------------------------------
30a = 19,260
------- -----------
30 30
a = 642
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I just realized that there can't be a negative amount of children, so I'm sorry if these results are all wrong.