Answer:
Fraction of the people chose a tart =
Step-by-step explanation:
Given - A group of people went to a coffee shop. Each person chose a
drink and a treat. number of people who chose coffee: number of
people who chose tea = 1:4. Of those who chose coffee, number of
people who chose a muffin number of people who chose a tart =
2:7. Of those who chose tea, number of people who chose a muffin
: number of people who chose a tart = 5:1.
To find - What fraction of the people chose a tart?
Proof -
Let the Total number of People went to a coffee shop = 5x
Now,
As given, number of people who chose coffee: number of people who chose tea = 1:4
⇒Total number of people who chooses coffee =
= x
Total number of people who chooses tea =
= 4x
Now,
As given,
Of those who choose coffee, number of people who chose a muffin number of people who chose a tart = 2:7
⇒Total number of people who choose muffin after coffee = ![\frac{2}{9}x](https://tex.z-dn.net/?f=%5Cfrac%7B2%7D%7B9%7Dx)
Total number of people who choose tart after coffee = ![\frac{7}{9}x](https://tex.z-dn.net/?f=%5Cfrac%7B7%7D%7B9%7Dx)
Also,
Given that
Of those who chose tea, number of people who chose a muffin : number of people who chose a tart = 5:1
⇒Total number of people who choose muffin after tea = ![\frac{5}{6}.4x = \frac{20}{6}x](https://tex.z-dn.net/?f=%5Cfrac%7B5%7D%7B6%7D.4x%20%3D%20%5Cfrac%7B20%7D%7B6%7Dx)
Total number of people who choose tart after tea = ![\frac{1}{6}.4x = \frac{4}{6}x](https://tex.z-dn.net/?f=%5Cfrac%7B1%7D%7B6%7D.4x%20%3D%20%5Cfrac%7B4%7D%7B6%7Dx)
∴ we get
Total number of people who chooses tart = Total number of people who choose tart after coffee + Total number of people who choose tart after tea
⇒Total number of people who chooses tart =
+
= ![\frac{7}{9}x + \frac{2}{3}x](https://tex.z-dn.net/?f=%5Cfrac%7B7%7D%7B9%7Dx%20%2B%20%5Cfrac%7B2%7D%7B3%7Dx)
= ![\frac{7x + 6x}{9}](https://tex.z-dn.net/?f=%5Cfrac%7B7x%20%2B%206x%7D%7B9%7D)
= ![\frac{13}{9}x](https://tex.z-dn.net/?f=%5Cfrac%7B13%7D%7B9%7Dx)
⇒Total number of people who chooses tart = ![\frac{13}{9}x](https://tex.z-dn.net/?f=%5Cfrac%7B13%7D%7B9%7Dx)
Now,
Fraction of the people chose a tart = ![\frac{People choose tart}{Total people}](https://tex.z-dn.net/?f=%5Cfrac%7BPeople%20choose%20tart%7D%7BTotal%20people%7D)
= ![\frac{\frac{13}{9}x }{5x}](https://tex.z-dn.net/?f=%5Cfrac%7B%5Cfrac%7B13%7D%7B9%7Dx%20%7D%7B5x%7D)
=
⇒Fraction of the people chose a tart =