Question

The table shows the relative investment in alternative energy sources in the United States by tye. One column shows the relative investment in $2007$ of $\$75$ million total invested in alternative energy. The other column shows the projected relative investment in $2017$ given current trends. The total projected investment in alternative energy in $2017$ is $\$254$ million. Suppose that a new source of alternative energy, Cold Fusion, is perfected. It is projected that by $2017$ that $\$57$ million will be invested in Cold Fusion in the United States, without any corresponding reduction in investment for any other form of alternative energy. What portion of the total investment of alternative energy in the United States will be sent on biofuels?
The United States Investment in Alternative Energy Sources

	Actual $2007$ Investment	Projected $2017$ Investment
Biofuels	$0.31$	$0.34$
Wind	$0.40$	$0.32$
Solar	$0.27$	$0.30$
Fuel Cells	$0.02$	$0.04$
Total	$1.00$	$1.00$

• A. $0.18$
• B. $0.22$
• C. $0.28$
• D. $0.34$

Answer 1

The correct option is C $0.28$

$\Rightarrow$ The new proportion must be less than the current $0.34$ for bio-fuels, because the total amount spent on alternative energy is increasing, but the amount spent on Bio-fuels is remaining the same.

$\Rightarrow$ So, answer will not be option $D$

$\Rightarrow$ Next, determine the amount that will be spent on bio-fuels in $2017$ by multiplying $0.34$ by the total of $\$254million:0.34\times 254=\$86.36million.$

$\Rightarrow$ Because $57$ million new dollars will be spent on alternative energy, the new total will be $=254+57=\$311million$

$\Rightarrow$ Divide $\$86.36$ million by $\$311$ million to get the new proportion $=\frac{86.36}{311}=0.28$