Bruchteile von Mengen und Größen
About this app
¾ von 24 Kugeln oder ¾ von 2,80 €: Das Ganze wird auf so viele Schalen verteilt, wie der Nenner sagt, dann werden so viele Schalen gesammelt, wie der Zähler sagt. Mit Strecke und Uhr, Rückwärtsrechnen zum Ganzen, Schalter „Falsch herum rechnen“ (24 : 3 · 4 ergibt mehr als das Ganze) und Übungsaufgaben mit Rückmeldung.
With explain mode: an AI tutor walks you through the app, points out what matters in the scene and answers your questions.
How to find a fraction of an amount
A fraction of an amount tells you which share of a whole is meant. You work out ¾ of 24 in two steps. First divide the whole by the denominator, because the denominator says into how many equal parts it is split: 24 : 4 = 6. Then multiply by the numerator, because it says how many parts are taken: 3 · 6 = 18. Quantities work the same way: ¾ of €2.80 is €2.10, ¾ of an hour is 45 minutes. If you know the part and look for the whole, work backwards: first divide by the numerator, then multiply by the denominator.
What the app shows
At the top lies the whole, for example 24 marbles or 28 coins of 10 cents. When sharing out, they move in turn into as many bowls as the denominator says, and a bracket marks one part. When collecting, as many bowls as the numerator says move down. On the right are the fraction in stacked form and the calculation chain with the steps “: denominator” and “· numerator”; each value appears only after its step. Lengths are shown as a strip with a ruler, time as a clock.
Try it yourself
Set the numerator, denominator and the whole with plus and minus, choose set, money, time or length and work forwards or backwards to the whole. Tap a bowl to change the numerator. The “Wrong way round” switch divides 24 by 3 and multiplies by 4: then a bowl is missing and the result is 32 marbles, more than the whole. The Practice panel has short random tasks that recognise typical mistakes and play the solution in the scene.
Frequently asked questions
- How do you work out ¾ of €2.80?
- Divide €2.80 by the denominator 4, which gives €0.70, and multiply by the numerator 3: €0.70 · 3 = €2.10. Working in cents often helps: 280 ct : 4 = 70 ct, 70 ct · 3 = 210 ct.
- Why is ¾ of 24 not 24 : 3 · 4?
- The denominator tells you into how many equal parts the whole is split, so you divide by 4. Dividing by 3 and multiplying by 4 gives 32, which is more than the whole. But a fraction like ¾ is less than 1, so its part of an amount is less than the whole.
- How do you find the whole when the part is known?
- Divide the part by the numerator and multiply by the denominator. If 18 marbles are ¾ of the whole, one quarter is 18 : 3 = 6 marbles and the whole is 4 · 6 = 24 marbles.
- What can I try in the app?
- Apply fractions with denominators up to 12 to sets of up to 60 marbles, amounts of money up to €6, one to three hours and lengths up to 60 m, work forwards and backwards, look at the “wrong way round” mistake and solve tasks with feedback in the Practice panel.
Subject: Bruchrechnung (Klasse 6)
More from Bruchrechnung (Klasse 6)
- Bruch-Werkstatt: Was ein Bruch bedeutet
- Brüche addieren und subtrahieren
- Brüche als Dezimalzahl und Prozent
- Brüche dividieren: Wie oft passt es hinein?
- Brüche multiplizieren mit kreuzweisem Kürzen
- Brüche multiplizieren: Anteil vom Anteil
- Brüche vergleichen und ordnen
- Dividieren mit dem Kehrwert
A VisuApp by heyprof: interactive, free in your browser, no sign-up. What is a VisuApp? · All apps