Institution: EXIM BANK LTD Exam: Exim Bank Ltd - Senior Officer - 30.12.2011 ||
Topic: Algebra Mathematics (বীজগণিত), Subject: Mathematics (সাধারণ গণিত)

Best Answer Explained in Below-:

<p data-sourcepos="1:1-1:46" style="margin-right: 0px; margin-left: 0px; white-space-collapse: preserve; word-break: break-word; color: rgb(31, 31, 31); font-family: &quot;Google Sans&quot;, &quot;Helvetica Neue&quot;, sans-serif; font-size: 16px;">Let x be the number of students in each class. </p><p data-sourcepos="3:1-3:47" style="margin-top: 1rem; margin-right: 0px; margin-left: 0px; white-space-collapse: preserve; word-break: break-word; color: rgb(31, 31, 31); font-family: &quot;Google Sans&quot;, &quot;Helvetica Neue&quot;, sans-serif; font-size: 16px;"><span style="font-weight: 700;">Number of absent students in each category: </span></p><ul data-sourcepos="5:1-8:0" style="margin-top: 4px; margin-bottom: 4px; padding-inline-start: 1.125rem; color: rgb(31, 31, 31); font-family: &quot;Google Sans&quot;, &quot;Helvetica Neue&quot;, sans-serif;"><li data-sourcepos="5:1-5:61">Half-full classes (5): (1/2) * x * 5 = 5x/2 students absent</li><li data-sourcepos="6:1-6:60">3/4 full classes (3): (1/4) * x * 3 = 3x/4 students absent</li><li data-sourcepos="7:1-8:0">1/8 empty classes (2): (1 - 1/8) * x * 2 = (7/8) * 2x = 7x/4 students absent</li></ul><p data-sourcepos="9:1-9:26" style="margin-top: 1rem; margin-right: 0px; margin-left: 0px; white-space-collapse: preserve; word-break: break-word; color: rgb(31, 31, 31); font-family: &quot;Google Sans&quot;, &quot;Helvetica Neue&quot;, sans-serif; font-size: 16px;"><span style="font-weight: 700;">Total absent students:</span></p><p data-sourcepos="11:1-11:71" style="margin-top: 1rem; margin-right: 0px; margin-left: 0px; white-space-collapse: preserve; word-break: break-word; color: rgb(31, 31, 31); font-family: &quot;Google Sans&quot;, &quot;Helvetica Neue&quot;, sans-serif; font-size: 16px;">The total number of absent students is the sum of the above categories:</p><p data-sourcepos="13:1-13:29" style="margin-top: 1rem; margin-right: 0px; margin-left: 0px; white-space-collapse: preserve; word-break: break-word; color: rgb(31, 31, 31); font-family: &quot;Google Sans&quot;, &quot;Helvetica Neue&quot;, sans-serif; font-size: 16px;">(5x/2) + (3x/4) + (7x/4) = 70</p><p data-sourcepos="15:1-15:25" style="margin-top: 1rem; margin-right: 0px; margin-left: 0px; white-space-collapse: preserve; word-break: break-word; color: rgb(31, 31, 31); font-family: &quot;Google Sans&quot;, &quot;Helvetica Neue&quot;, sans-serif; font-size: 16px;"><span style="font-weight: 700;">Combining like terms:</span></p><p data-sourcepos="17:1-17:24" style="margin-top: 1rem; margin-right: 0px; margin-left: 0px; white-space-collapse: preserve; word-break: break-word; color: rgb(31, 31, 31); font-family: &quot;Google Sans&quot;, &quot;Helvetica Neue&quot;, sans-serif; font-size: 16px;">(10x + 3x + 7x) / 4 = 70</p><p data-sourcepos="19:1-19:12" style="margin-top: 1rem; margin-right: 0px; margin-left: 0px; white-space-collapse: preserve; word-break: break-word; color: rgb(31, 31, 31); font-family: &quot;Google Sans&quot;, &quot;Helvetica Neue&quot;, sans-serif; font-size: 16px;">20x / 4 = 70</p><p data-sourcepos="21:1-21:49" style="margin-top: 1rem; margin-right: 0px; margin-left: 0px; white-space-collapse: preserve; word-break: break-word; color: rgb(31, 31, 31); font-family: &quot;Google Sans&quot;, &quot;Helvetica Neue&quot;, sans-serif; font-size: 16px;"><span style="font-weight: 700;">Solving for x (number of students per class):</span></p><p data-sourcepos="23:1-24:21" style="margin-top: 1rem; margin-right: 0px; margin-left: 0px; white-space-collapse: preserve; word-break: break-word; color: rgb(31, 31, 31); font-family: &quot;Google Sans&quot;, &quot;Helvetica Neue&quot;, sans-serif; font-size: 16px;">x = 70 * 4 / 20
x = 20 students/class</p><p data-sourcepos="26:1-26:43" style="margin-top: 1rem; margin-right: 0px; margin-left: 0px; white-space-collapse: preserve; word-break: break-word; color: rgb(31, 31, 31); font-family: &quot;Google Sans&quot;, &quot;Helvetica Neue&quot;, sans-serif; font-size: 16px;"><span style="font-weight: 700;">Total number of students in the school:</span></p><p data-sourcepos="28:1-28:93" style="margin-top: 1rem; margin-right: 0px; margin-left: 0px; white-space-collapse: preserve; word-break: break-word; color: rgb(31, 31, 31); font-family: &quot;Google Sans&quot;, &quot;Helvetica Neue&quot;, sans-serif; font-size: 16px;">Since there are 10 classes with the same number of students, the total number of students is:</p><p data-sourcepos="30:1-32:29" style="margin-top: 1rem; margin-right: 0px; margin-left: 0px; white-space-collapse: preserve; word-break: break-word; color: rgb(31, 31, 31); font-family: &quot;Google Sans&quot;, &quot;Helvetica Neue&quot;, sans-serif; font-size: 16px;">Total students = x * 10
Total students = 20 students/class * 10 classes
Total students = 200 students</p><p data-sourcepos="34:1-34:68" style="margin-top: 1rem; margin-right: 0px; margin-left: 0px; white-space-collapse: preserve; word-break: break-word; color: rgb(31, 31, 31); font-family: &quot;Google Sans&quot;, &quot;Helvetica Neue&quot;, sans-serif; font-size: 16px;">Therefore, the total number of students in the school is <span style="font-weight: 700;">a) 200</span>.</p>