Answer:
Step-by-step explanation:
LEt the number be x.
2x - 5 = 3
2x = 3 + 5 = 8
x = 8/2 = 4
To solve the equation: add 5 to both sides and then multiply by 1/2.
Answer:
Step-by-step explanation:
Answer:
There were 26 students in his class and the teacher had 83 ml of the solution.
Step-by-step explanation:
Mr. Kohl has a "x" amount of solution, if he divides it by the number of students "n" he'll give each student 3 milliliters and have a left over of 5 milliliters. If the amount of solution Mr. Kohl had was "x + 21" then he'd be able to give each student 4 milliliters of the solution. From these informations we have:
x = 3*n + 5
(x + 21)/n = 4
x + 21 = 4*n
x = 4*n - 21
Now that we have two equations and two variables we can solve the system of equations, as seen bellow:
3*n + 5 = 4*n - 21
3*n - 4*n = -21 - 5
-n = -26
n = 26
x = 4*26 - 21 = 83 ml
There were 26 students in his class and the teacher had 83 ml of the solution.
Given that the volume of a cell is 50 cubic micrometers. It says to find the number of cells present in 1 cubic centimeter.
So we need to first convert the units of volume of a cell, then we can find the total number of cells in 1 cubic centimeter.
We know 1 meter = 100 centimeters = 1000000 micrometers
So 1 centimeter = 10000 micrometers
Taking Cubic powers on both sides :-
1 cubic centimeters = 10¹² cubic micrometers
1 cubic micrometers = 10⁻¹² cubic centimeters
50 cubic micrometers = 50 × 10⁻¹² = 5 × 10⁻¹¹ cubic centimeters
So volume of one cell = 5 × 10⁻¹¹ cubic centimeters
Number of cells = 
= 2 × 10¹⁰ cells.
So, total number of cells = 2 × 10¹⁰ cells.
