The length and breadth of a metal sheet are 3.124m and 3.002 m respectively. the area of this sheet up to the correct number of significant
The length and breadth of a metal sheet are 3.124m and 3.002 m respectively. the area of this sheet up to the correct number of significant figure  is


A) 9.378 m2


B) 9.37 m2 


C)9.378248 m2


D)9.3782 m2
Correct option is A) 9.378 m2


![](https://lh3.googleusercontent.com/-UueuqyijXPQ/YLtK0v0m9CI/AAAAAAAABro/xFcfQOQAOx8jHAtpqiORvW_8DRFX1yK3ACLcBGAsYHQ/image.png)


result must have significant figures equal to least figures being multiplid do area of metal sheet 9.378 m2  (four significant digits)
you don't say that the area must be a rectangle. the true largest area would be a circle, with the circumference equal to 400m and the area would be 12,732.4 m^2. however, evidently, the area is restricted to a rectangle, in which case the maximum area is a square, and the side of the square will be 
400/4 = 100 m. the area is 100x100 = 10,000 m^2.
algebraically,
let x = one pair of opposite sides
(400-2x)/2 = 200-x = the other pair of opposite sides

area = a(x) = x(200 - x) = -x^2 + 200x
x-coordinate of vertex = -b/2a = 200/2 = 100
a(100) = 10,000

that's it! ;) ![](https://s3mn%20mnimgs%20com/img/shared/discuss_editlive/4110270/2012_11_30_15_28_05/vvnzofse6383734697724592802%20png)


let the length of path be a m


total area ![](https://s3mn%20mnimgs%20com/img/shared/discuss_editlive/4110270/2012_11_30_15_28_05/ceaxujzx7923478049123545928%20png)


area of lawn = total area â€“ area of
path

![](https://s3mn%20mnimgs%20com/img/shared/discuss_editlive/1800204/2012_12_04_21_09_56/mathmlequation2002748073868866733%20png)


area of lawn


![](https://s3mn%20mnimgs%20com/img/shared/discuss_editlive/4110270/2012_11_30_15_28_05/dwqusyms3311632565229211681%20png) the dimensions of base of a rectangular box of greatest volume that can be constructed from 100 cm square of hard board sheet, if the box is three times as long as it is wide, are \_\_\_\_\_\_. the straight distance between two place on a map can be measured by a strip of paper and divider.use a ruler to measure the distance between the two places. if the line is quite curved, use a string to determine the distance, and then measure the string. find the scale for the map you're going to use. it might be a ruler bar scale or a written scale, in words or numbers. area of trapezium = area of trapezium = = therefore = 24 cm the centimetre (cm) is a unit of length in the metric system, equal to one-hundredth of a meter. the millimetre (mm) is a unit of length in the metric system, equivalent to one-thousandth of a meter and is the si base unit of length. 1 mm = 1/10 cm 1 mm = 0.1 cm to convert the unit of length in millimetres to centimetres follow the below steps: take the value of length in millimetres and multiply it by 0.1 cm the obtained value is the answer in centimetres 25mm x 0.1cm= 2.5 cm answer hence, 25 mm = 2.5cm Correct answer is 26 mm. Mass of powder is constant. mi=mf  ⇒ ρiVi = ρfVf ρihi = ρf hf ⇒ hi = (ρf hf)/ρi On substitution, (1755×12)/ 810= 26 mm  


Correct answer is 26 mm.


Mass of powder is constant.


mi=mf ⇒ ρiVi= ρfVf


ρihi = ρf hf⇒ hi = (ρf hf)/ρi


On substitution, (1755×12)/ 810= 26 mm


 


[See less](#) radius = 1.75 m
height (h) = 12 m
volume = 
= ×  × 1.75 × 1.75 × 12
= 38.5 m3
since, 1 m3 = 1 kiloliter
capacity of the pit = (38.5 × 1)
= 38.5 kilolitres given: volume of cylinder = 1617 cm3let r be the radius of base and h be the height of coner:h = 2:3∴ r/h = 2/33r = 2hh = 3r/2 …(i)formula: volume of cylinder = πr2h∴ 1617 = (22/7) r2hr2h = 514.5using (i) we have∴ r2 × (3r/2) = 514.53r3 = 1029r3 = 343r = 7 cmh = 21/2 cmtotal surface area of cylinder = 2πr2 + 2πrh= 2 × (22/7) × 72 + 2 × (22/7) × 7 × (21/2)= 308 + 462= 770 cm2therefore total surface area of cylinder = 770 cm2 18 sq.units explanation: x2 = 12y ∴ 4b = 12 ∴ b = 3 area of triangle = `1/2 xx "ab" xx "os"` = `1/2 xx 4"a" xx "a"` = `1/2(12)(3)` = 18 sq. units