standard_description: Determine the unknown whole number in an addition or subtraction equation relating to three whole numbers. For example, determine the unknown number that makes the equation true in each of the equations 8 + ? = 11, 5 = �� – 3, 6 + 6 = ��.
problem_activity: Task
A government buys $x$ fighter planes at $z$ dollars each,
and $y$ tons of wheat at $w$ dollars each. It spends a total of $B$
dollars, where $B = xz + yw$. In (a)–(c), write an
equation whose solution is the given quantity.
The number of tons of wheat the government can afford to buy if it
spends a total of \$100 million, wheat costs  \$300 per ton, and it must
buy 5 fighter planes at \$15 million each.
The price of fighter planes if the government bought 3 of them, in addition to $10,\!000$ tons of wheat at \$500 a ton, for a total of \$50 million.
The price of a ton of wheat, given that a fighter plane costs $100,\!000$ times as much as a ton of wheat, and that the government bought 20 fighter planes
and $15,\!000$ tons of wheat for a total cost of
\$90 million.


aligns: no