Answer:
7 , or 7/1
Step-by-step explanation:
Let ? = x. Set the equation:
(3/10)x = 21/10
Isolate the variable, x. Multiply 10/3 to both sides of the equation:
x * (3/10) * (10/3) = (21/10) * (10/3)
x = 21/10 * 10/3
Simplify the equation. Divide common factors from both the numerator and denominator, and then simplify:
x = (21 * 10)/(10 * 3)
x = (21/3) = 7/1 = 7
x = 7