Page 157 - Bangladesh_classwiz_BOOK2018_rev_Neat

GLb K¨vjKz‡jUiwU GK Pj‡Ki gvb †bIqvi Rb¨ cÖ¯‘Z, hv c~‡e© GK Pj‡Ki Av‡jvPbvq e¨vL¨v Kiv n‡q‡Q| c~‡e©i
b¨vq GK Pj‡Ki Z_¨ DcvË mg~n K¨vjKz‡jU‡i cÖ‡ek Kiv‡Z n‡e| Z‡e c~‡e© Avgiv Z_¨-Dcv‡Ëi we‡kølY K‡iwQ,
GLb Avgiv cwiwg‡Zv web¨vm Kie| cwiwg‡Zv web¨vm Kivi Rb¨ Mo (Mean), cwiwg‡Zv e¨eavb (standard
deviation) Ges †f`v¼ (Variance) Rvbv _vK‡Z n‡e, hv GK Pj‡Ki we‡kølY n‡Z Rvbv hv‡e|

GLb, C evUb †P‡c TR Pvc‡j wb‡¤œvv³ w¯Œb¸‡jv †`Lv hv‡e|

Gici 4 evUb Pvc‡j, cwiwg‡Zv web¨v‡mi option (evQvB¸‡jv) †`Lv hv‡e, hv Dc‡ii 3q w¯Œ‡b †`Lv‡bv
n‡jv|

D³ Option ¸‡jv n‡Z, †h‡Kv‡bv gv‡bi Rb¨ cÖ‡qvRbxq A‡ji m¤¢veZv †ei Kiv hvq| †hgb, g‡b Kwi, =

1. Zvn‡j, Dc‡ii cwiwg‡Zv †iLv wPÎ 02 n‡Z,

(1) = (1) − 0.5 Ges (1) = 1 − (1) = 0.5 − (1)

K¨vjKz‡jUi Gi mvnv‡h¨ Zv mn‡RB †ei Kiv hvq| Zvi Rb¨ 1 evUb †P‡c evQvBwU wb‡q Avevi 1 †P‡c

= evUb Pvc‡Z n‡e| Avevi evQvBwUi Rb¨ 2 evUb †P‡c 1 w`‡q =evUb Pvc‡Z n‡e Ges evQvBwUi
Rb¨ 3 w`‡q 1= evUb Pvc‡Z n‡e| hv wb‡Pi w¯Œb¸‡jv †`Lv hv‡e|

‡h‡nZz cwiwg‡Zv web¨vm = 0 †Z cÖwZmg, A_©vr

≤ −1 Gi m¤¢vebv = ≥ 1Gi m¤¢vebv

Dc‡ii cwiwg‡Zv †iLvi wPÎ n‡Z Zv mn‡RB eySv hvq| Gi gvb abvZ¥K ev FYvZ¥K Df‡qi Rb¨ gvb †ei Kiv
hvq| hv wb‡Pi w¯Œ‡b †`Lv‡bv n‡jv-

Dc‡ii 2q wPÎ Gi g‡Zv Avgiv Lye mn‡RB e¨ewai m¤¢vebv †ei Ki‡Z cvwi| †hgb −0.5 ≤ ≤ 1.5 Gi
m¤¢vebv †ei Ki‡Z, ( ≤ 1.5 Gi m¤¢vebv) − ( ≤ −0.5 Gi m¤¢vebv) = 0.62465 [2q wP‡Î n‡Z]

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