Lena reads 3/8 of a book on Monday and 1/4 of it on Tuesday. She still has 45 pages to read. How many pages are in the book?
Answer and explanation
Correct answer: C. 120
- Step 1: She has read 3/8 + 2/8 = 5/8, leaving 3/8. Step 2. 3/8 of the book = 45 pages, so 1/8 = 15 pages. Step 3. The whole book is 8 × 15 = 120 pages. Answer: 120. Why not the others: 72: This treats the 45 pages as the 5/8 she has already read. 135: This multiplies 45 by 3 for no reason connected to the fractions. 360: This multiplies 45 by 8, the denominator.
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