Question
After swapping its digits, a two-digit number becomes
17 less than 200% of the original number. The sum of the digits is 8. Find the original number.Solution
Let tens = x, units = y. Original = 10x + y, swapped = 10y + x. 10y + x = 2(10x + y) − 17 ⇒ 10y + x = 20x + 2y − 17 ⇒ 19x − 8y = 17 … (I) x + y = 8 … (II) Multiply (II) by 8 and add to (I): (19x − 8y) + (8x + 8y) = 17 + 64 ⇒ 27x = 81 ⇒ x = 3 y = 8 − 3 = 5 Original number = 10×3 + 5 = 35
What approximate value will come in place of question (?) in the following given expression? You are not expected to calculate the exact value.
...3.934 - 124.07 + 35.94 + 12.83 of 4.85 - 84.76 ÷ √26 = ?3
- What approximate value will come in place of the question mark (?) in the following question? (Note: You are not expected to calculate the exact value.)
- What approximate value will come in place of the question mark (?) in the following question? (Note: You are not expected to calculate the exactvalue.)
(1680.23 ÷ 27.98) + (600.32 ÷ 23.9) + 1384.11 = ?
What approximate value should replace the question mark?
27.48% of 600.06 + ?% of 200.01 = 284.94
(44.79 × 74.21) ÷ (11.862 – 33.12) + 37.48% of ? = 180.23
2090.03 ÷ 54.98 x 49.9 = ? + 20.32
√92.10 + √256.30 + 60.78% of (420.90 + 19.36% of 140.25) = ?
(22.03 + 89.98) ÷ 14.211 = 89.9 – 25.23% of ?
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