Given:
The width of a kitchen is 4.2 metres.
Kitchen cupboard widths are 60 cm.
To find:
The number of kitchen cupboard that will fit in 4.2 metres.
Solution:
Let x be the number of kitchen cupboard that will fit in 4.2 metres.
Width of 1 cupboard = 60 cm
Width of x cupboards = 60x cm
We know that, 1 m = 100 cm.
Width of a kitchen = 4.2 metres
= 4.2×100 cm
= 420 cm
Now, the width of the x cupboards is equal to width of the kitchen.



Therefore, the number of kitchen cupboard that will fit in 4.2 metres is 7.
The numbers are:
3.9 × 105 = 409.5
6.1 ×103 = 628.3
9.3 × 105 = 976.5
1.6 × 103 = 164.8
Arranging from greatest to least and in scientific notation form gives:
9.3 × 105 , 6.1 × 103 , 3.9 × 105 , 1.6 × 103
*(Seems like there is no correct answer from the choices given there).
You just substitute the value of x in the given equation:
f(x) = 2x^2 - 5
f(-4) = 2 (-4)^2 -5 = 27
f(x) : a name given to the equation
f(-4): refer to the equation when the value of the independent variable x has the value between the brackets.
The starting percent is 100%. After one hour, bacteria tripled, so it is 300%.