Question

Difficulty: EasyNumber Bases and Conversions

If 32x=231032_x = 23_{10}, find the value of the base xx.

Answer: 7

Answer

7
Expanding the number 32x32_x into base 10 gives 3×x+2=3x+23 \times x + 2 = 3x + 2. Setting 3x+2=233x + 2 = 23 leads to 3x=213x = 21, giving x=7x = 7.

Step-by-Step Solution

1
Expand 32x32_x in terms of powers of xx
3x+23x + 2
In base xx, the rightmost digit has a weight of x0=1x^0 = 1 and the next digit to the left has a weight of x1=xx^1 = x.
2
Equate the expanded form to the given base 10 value and solve for xx
x=7x = 7
Setting 3x+2=233x + 2 = 23 gives 3x=213x = 21, which yields x=7x = 7 upon dividing by 3.

Key Concept

Expansion and conversion from Base x to Base 10
Estimated Time:45s
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