Universal advice on how to write VLOOKUP in mathematics perfectly well: go over all the topics, identify the most difficult tasks, work them out and try not to worry on the test. In theory, everything sounds simple, but in practice, on the eve of VLOOKUP, each topic seems difficult. What topics cause the most questions among schoolchildren of different grades, and how can parents be helped?
Grade 5: Interest
Adults themselves are confused with interest, that then they have to overpay for a loan more than they expected. What can we say about children for whom it is still a dark forest full of abstract numbers: “what does 25% of 60 mean? And why is it the same as 5% of 300?”.
First, discuss with your child that one percent is a fraction of a whole number divided by 100, a few percent is one percent multiplied by the desired number. And then explain using an example close to the child: if Petya started watching a 10-minute video and turned it off after 8 minutes, it means that he watched 80% of the video.
Grade 6: Negative numbers and modulus
The student goes to the 6th grade, and there everything is new, only with negative numbers. Together with the child, draw a coordinate line, that is, an endless row, in which each next number is greater than the previous one. In the center of this row there will be the number 0 - negative numbers will go before it, after it - positive ones.
On the same coordinate line, you can then explain the modulus of the number - the distance from the origin to the point of the coordinate line corresponding to this number. For clarity, you can select a negative number and show the distance from it to zero, and then do it with the same positive number in absolute value - these distances will coincide.
Grade 7: Linear Equations
The terrible dream of any schoolchild is equations. As if mathematicians are missing calculations with known ones! Alas, not enough … On VLOOKUP seventh-graders will be tested for their ability to solve linear equations, that is, equations with variables in degree 1.
In textbooks, equations are written as an expression with x. Try to visualize it, for example: There were several bottles of cola in the fridge (this is x), and Petya put two more bottles of Pepsi there. When my mother opened the refrigerator, she saw 7 bottles (or in mathematical terms, x + 2 = 7). How many cola bottles were in the fridge originally? (or what is x?)
Grade 8: Geometry
Childhood ends when the child begins to separate algebra and geometry. But eighth-graders are already adults and they cannot be surprised by the question of how a straight line, a segment and a ray differ from each other. But on the test there will be triangles, medians and bisectors, cosines and sines.
Before the VLOOKUP, repeat with the student all the theorems and properties of triangles, for example, that the sum of the angles in a triangle is 180 °. This will help to easily solve a problem like the following: the bisector CE is drawn in the triangle ABC. Find the angle BCE if ∠BAC = 46 ° and ∠ABC = 78 °. First, we find the angle ∠BCA and for this we subtract the angle 46 ° and 78 ° from the total 180 °, so ∠BCA = 56 °. And the bisector divides the angle in half, so ∠BCE = 56 ° / 2 = 28 °.
Do not forget that it is better to deal with difficult topics in the class in which the child encountered them. This is how misunderstanding will not turn into a snowball, with which the student will have to deal with before the OGE and the Unified State Exam.