Hey there!
We see that 90 hazel nuts have a mass of 125 g. First, let's find the ratio of hazelnuts to calories. First, we will want to get down to 100 grams of hazelnuts.
![(hazelnuts)/(grams) = (90)/(125) =(h)/(100)](https://img.qammunity.org/2019/formulas/mathematics/middle-school/yeha7320ne9rpuh06j8v5intrbs4ju17rc.png)
We cross multiply and solve for h.
125h=9000
We divide both sides by 125.
h=72
Therefore, 72 hazelnuts have 630 calories. We can plug this into a new proportion and see how many calories one hazelnut has.
![(hazelnuts)/(calories) = (72)/(630) =(1)/(c)](https://img.qammunity.org/2019/formulas/mathematics/middle-school/rs3wqdtye1fsl78rwcmtkz0rldhw1kulk3.png)
We cross multiply and solve for c.
72c=630
We divide both sides by 72.
c= 8.75
Therefore, one hazelnut contains 8.75 calories.
I hope this helps!