Question

I spent a quarter of my money and then received an amount equal to twice the money I had left. If I now have 30 euros more than at the beginning, how many euros did I have?

136

likes

680 views

Answer to a math question I spent a quarter of my money and then received an amount equal to twice the money I had left. If I now have 30 euros more than at the beginning, how many euros did I have?

$Expert avatar$

Gerhard

4.5

92 Answers

Llamemos x euros a la cantidad de dinero con la que empezaste. Después de gastar un cuarto, te quedan 3x/4 euros. Luego, recibes el doble del dinero que te quedaba, que es 2*(3x/4) = 3x/2 euros. La cantidad total que tienes ahora es 3x/4 (dinero restante) + 3x/2 (dinero recibido) = 9x/4 euros. Como son 30 euros más de lo que empezaste, podemos escribir la ecuación: 9x/4 = x + 30 Resolviendo para x: Multiplica ambos lados por 4 para deshacerte de la fracción: 9x = 4x + 120 Resta 4x de ambos lados para aislar x: 5x = 120 Divide ambos lados por 5 para encontrar x: x = 24 Por lo tanto, originalmente tenías 24 €.

Frequently asked questions (FAQs)

Question: Solve for x: log(base 5) (x+3) = 2

What is the derivative of f(x) = 3x^4 - 2x^3 + 5x^2 - 4x + 7?

Math question: Find the length of the hypotenuse in a right triangle with legs measuring 7cm and 11cm.

New questions in Mathematics

Solution of the equation y'' - y' -6y = 0

Let the vectors be u=(-1,0,2) , v=(0,2,-3) , w=(2,2,3) Calculate the following expressions a)<u,w> b) <2u- 5v,3w>

A circle with a 12-inch diameter is folded in half and then folded in half again. What is the area of the resulting shape?

two particles start at the origin and move along the x axis. for 0 <= t <= 10, their respective position functions are given by x1 = cos(t) and x2 = (e^-3t) + 1. for how many values of t do the particles have the same velocity?

You have been hired to estimate the average weight of quarters in circulation. Based on the sample of quarters you collect (below), create a 90% confidence interval for the weight of quarters in circulation. Quarter Weights (grams) 5.631 5.714 5.719 5.689 5.551 5.723 5.705 5.627 5.627 5.715 5.576 5.632 5.641 5.676 5.660 5.699 5.609 5.634 5.713 5.591 5.674 5.675 5.684 5.694 5.655 5.632 5.598 5.675 5.628 5.562 5.636 5.583 5.567 5.551 5.649 5.708 5.696 5.614 5.637 5.601 5.628 5.711 5.566 5.653 5.653 5.597 5.687 5.717 5.678 5.654 5.556 5.707 5.563 5.628 5.679 5.714 5.555 5.719 5.634 5.647 5.717 5.612 5.705 5.657 5.670 5.607 5.687 5.666 5.612 5.718 5.714 5.713 5.663 5.641 5.589 5.656 5.712 5.639 5.577 5.580 5.674 5.636 5.625 5.597 5.616 5.591 5.616 5.700 5.706 5.695 5.562 5.699 5.607 5.573 5.659 5.632 5.654 5.568 5.628 5.687 5.605 5.689 5.687 5.554 5.618 5.701 5.681 5.645 5.714 5.665 5.661 5.634 5.714 5.586 5.656 5.673 5.657 5.717 5.611 5.578 5.579 5.614 5.644 5.724 5.647 5.566 5.697 5.558 5.586 5.586 5.611 5.573 5.573 5.709 5.629 5.649 5.552 5.615 5.645 5.611 5.686 5.588 5.641 5.704 5.703 5.696 5.557 5.551 5.725 5.608 5.725 5.603 5.677 5.638 5.573 5.640 5.561 5.631 5.563 5.671 5.662 5.569 5.648 5.680 5.681 5.551 5.555 5.578 5.701 5.645 5.670 5.574 5.594 5.705 5.633 5.719 5.680 5.647 5.641 5.553 5.616 5.698 5.552 5.566 5.559 5.697 5.686 5.560 5.629 5.701 5.622 5.615 5.553 5.608 5.637 5.663 5.696 5.714 5.675 5.613 5.594 5.669 5.569 5.716 5.705 5.603 5.709 5.717 5.606 5.581 5.575 5.601 5.600 5.664 5.715 5.705 5.583 5.586 5.592 5.550 5.628 5.662 5.603 5.559 5.676 5.558 5.678 5.671 5.642 5.581 5.568 5.706 5.665 5.712 5.574 5.602 5.699 5.716 5.693 5.711 5.635 5.612 BLANK #1: Is this a question involving mean or proportion? ***ANSWER "MEAN" OR "PROPORTION" (WITHOUT THE QUOTATION MARKS)*** BLANK #2: What is the LOW end of the estimate ***ANSWER TO 3 DECIMALS*** BLANK #3: What is the HIGH end of the estimate ***ANSWER TO 3 DECIMALS***

Estimate the fifth term if the first term is 8 and the common ratio is -1/2

4. Show that if n is any integer, then n^2 3n 5 is an odd integer