Answer:
She consumes 30 blue ray disk and 60 DVD respectively.
Explanation:
Consider the provided information.
![U(x,y)=10x^2y](https://img.qammunity.org/2020/formulas/mathematics/college/e0f6cirgn4le7lzbvycdwuw4e3zszcpyvq.png)
Calculate marginal utility of good
Differentiate with respect of x and y.
![MU_x=20xy](https://img.qammunity.org/2020/formulas/mathematics/college/tpbyusn2dlwdckcu2erjginxmav093xp79.png)
![MU_y=10x^2](https://img.qammunity.org/2020/formulas/mathematics/college/86dj15hir4rs4r3soqkklewbcdto4xhmvd.png)
Her consumption of Blu-ray disks (X) with a price of $40 and Y is her consumption of DVDs with a price of $10.
The ratio of marginal utility of good x to y is equal to the price ratio:
![(MU_x)/(MU_y)=(P_x)/(P_y)](https://img.qammunity.org/2020/formulas/mathematics/college/qzfdlb6ibaqhnfd2rwncfugme6hnn9f64k.png)
Substitute the respective values.
![(20xy)/(10x^2)=(40)/(10)](https://img.qammunity.org/2020/formulas/mathematics/college/ixt7788xbcumwe0a8p8pxq1josfvac8xx1.png)
![(2y)/(x)=4](https://img.qammunity.org/2020/formulas/mathematics/college/i7ritegao7j5vsphmsa9slutjs56gyewme.png)
![2y=4x](https://img.qammunity.org/2020/formulas/mathematics/college/jpm3atzbtt2jlqgtwj3rjripu6wqlz0u1t.png)
![y=2x](https://img.qammunity.org/2020/formulas/mathematics/middle-school/qeikkehr3tck2vx09s7uvb1jwawqh078s6.png)
She has $1800 with which to spend on the two goods.
Her consumption of Blu-ray disks (X) with a price of $40 and Y is her consumption of DVDs with a price of $10. She has $1800 with which to spend on the two goods.
Therefore,
![40x+10y=1800](https://img.qammunity.org/2020/formulas/mathematics/college/4g1iua0tcggqt85rsfvm2dnp2j89g7c4wg.png)
![4x+y=180](https://img.qammunity.org/2020/formulas/mathematics/college/wb2yes6g6yji8z74tboc02s7wy6oqz3tp6.png)
Substitute the value of y in above equation.
![4x+2x=180](https://img.qammunity.org/2020/formulas/mathematics/college/pbewa2btcgg7tntdmvmf80ziwlwd0xpkrp.png)
![6x=180](https://img.qammunity.org/2020/formulas/mathematics/middle-school/hl1ofz2466u9w6njo8v8cgrfx1qx01gggy.png)
![x=30](https://img.qammunity.org/2020/formulas/mathematics/middle-school/uw6o3xm0tea8s8hlq6f1vol2c22er6no3y.png)
Thus,
![y=60](https://img.qammunity.org/2020/formulas/mathematics/middle-school/evkeo3pdcm02j48zdrb11mdasspb4coend.png)
She consumes 30 blue ray disk and 60 DVD respectively.