Question 27 of 27intermediate🔍 AnalyzeShort Answer3 marks

Which is larger? Find out without fully computing the product. (i) 14×2614 \times 26 or 16×2416 \times 24 (ii) 25×7525 \times 75 or 26×7426 \times 74

(i)
Answer

16×2416 \times 24 is larger. Both have sum 40, but 1616 and 2424 are closer to 2020 than 1414 and 2626, making their product larger.

(ii)
Answer

26×7426 \times 74 is larger. 26×74=192426 \times 74 = 1924 while 25×75=187525 \times 75 = 1875.

Explanation

(i) For fixed sum, product is maximized when factors are equal. 16×24=38416 \times 24 = 384, 14×26=36414 \times 26 = 364. (ii) Using Identity 1C: 26×74=(50−24)(50+24)=2500−576=192426 \times 74 = (50-24)(50+24) = 2500 - 576 = 1924. 25×75=(50−25)(50+25)=2500−625=187525 \times 75 = (50-25)(50+25) = 2500 - 625 = 1875.