# Can you explain why as well? There's a picture.

Jul 21, 2018

$196$.

#### Explanation:

Let ${t}_{m}$ denote the score in the ${m}^{t h}$ test.

Then, by given, $86 = \frac{{t}_{1} + {t}_{2} + {t}_{3} + {t}_{4}}{4.}$

$\therefore {t}_{1} + {t}_{2} + {t}_{3} + {t}_{4} = 4 \times 86 = 344. \ldots \ldots \ldots \ldots . . \left({\star}_{1}\right)$.

We are required to find ${t}_{5} + {t}_{6}$, such that,

$\frac{{t}_{1} + {t}_{2} + {t}_{3} + {t}_{4} + {t}_{5} + {t}_{6}}{6} = 90 ,$

$\mathmr{and} , {t}_{1} + {t}_{2} + {t}_{3} + {t}_{4} + {t}_{5} + {t}_{6} = 6 \times 90 = 540. . . \left({\star}_{2}\right)$.

Utilisig $\left({\star}_{1}\right) \text{ into } \left({\star}_{2}\right)$, we have,

${t}_{5} + {t}_{6} = 540 - 344 = 196$.