Respuesta :
The baker needs to use 100/3 pounds of 90% chocolate to make the cake.
Equation
An equation is an expression used to show the relationship between two or more numbers and variables.
Let x represent the amount of 90% chocolate. Using equation:
100 * 70% + x * 90% = (x + 100) * 75%
100 * 0.7 + 0.9 * x = (x + 100) * 0.75
70 + 0.9x = 0.75x + 75
x = 100/3
The baker needs to use 100/3 pounds of 90% chocolate to make the cake.
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