Answer:
We need 8 and 3/4 cups of blueberries to make 7 batches of pancakes.
Explanation:
A proportion is basically a statement that says two fractions are equal to each other. It's usually used to state the equivalence of two ratios, and is often in problems such as these, where you need to prove that the ratio of the original two objects are the same as the new two objects.
Let us set x to be the new amount of cups of blueberries.
Hence, we have to find the original ratio first. Let's say we want to use the ratio of cups of blueberries to batches to be the measuring stick (a quick tip would be to see what information is provided for the new ratio and use that information as the denominator). That ratio would be:
![(1 (1)/(4))/(1)](https://img.qammunity.org/2021/formulas/mathematics/high-school/u2k8jq1znf7piu83qhnm0wuy4xmscba58g.png)
![= ((5)/(4))/(1)](https://img.qammunity.org/2021/formulas/mathematics/high-school/fx6uzg31dd9rartrrwo9mqw20xgabytu79.png)
![= (5)/(4)](https://img.qammunity.org/2021/formulas/mathematics/high-school/7kqedivngxj0lu4dk4ty5bjc9obl7vg5dc.png)
So, now that we know the ratio of cups of blueberries to batches, we can use that information to construct a proportion:
![(5)/(4) = (x)/(7)](https://img.qammunity.org/2021/formulas/mathematics/high-school/vn6s7yvpvxl5wai1h143dewmgta5nijcjn.png)
Great! Now it's just a matter of solving this equation:
![(5)/(4) = (x)/(7)](https://img.qammunity.org/2021/formulas/mathematics/high-school/vn6s7yvpvxl5wai1h143dewmgta5nijcjn.png)
![4x = 5 \cdot 7](https://img.qammunity.org/2021/formulas/mathematics/high-school/n089fy7hzlcoc2sglo6tz8hi9jx3cfja7s.png)
![x = (35)/(4)](https://img.qammunity.org/2021/formulas/mathematics/high-school/pllkq4lk21bnjz50gfs8dl05klayxy9hjt.png)
![x = 8 (3)/(4)](https://img.qammunity.org/2021/formulas/mathematics/high-school/lueyg8amcf4qfa40jepwh32yco4bohm8hm.png)
Finally, we can know that we need 8 and 3/4 cups of blueberries to make 7 batches of pancakes.
Hope this helped!