Johnny

Johnny bought for 28 CZK flower to mum. He that spent 4/7 of the money saved. How much money he had saved? How much money left him?

Result

x =  49
x =  21

Solution:


28 = 4/7 x
y = x-28

-4x = -196
-x+y = -28

x = 49
y = 21

Calculated by our linear equations calculator.







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To solve this example are needed these knowledge from mathematics:

Do you have a linear equation or system of equations and looking for its solution? Or do you have quadratic equation? Most natural application of trigonometry and trigonometric functions is a calculation of the triangles. Common and less common calculations of different types of triangles offers our triangle calculator. Word trigonometry comes from Greek and literally means triangle calculation.

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