Average is defined as the middle value of a given sequence or series of numbers. it is calculated by the sum of all the numbers divided by the total numbers of values.
Given that:
Average = 98
Value 1 = 86
Value 2 = 87
Value 3 = 91
Value 4 = x
Let the Value 4 be x.
As we know,
[tex]\begin{aligned}\text {Average}&=\dfrac{\text{Sum of all the numbers}}{\text{Total number of the values}}\\\\ 98&=\dfrac{86 + 87 + 91 + x}{4}\\\\98&=\dfrac{264 + x}{4}\\\\98 \times 4 &= 264 + x\\392 &= 264 + x\\392 - 264 &= x \end{aligned}[/tex]
x = 128
Thus, the value of x = 128.
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