Câu số 9: The perimeter of a rectangle is 64cm and its length is 16cm more than its width.The area of this rectangle is ………..cm2 Câu số 11: Minh is 9 years old. If the average of age of Minh and his mother is 22, then his mother is ……….years old. Câu số 12: The sum of two numbers is 47 and their difference is 15. The smaller number is ……….. Câu số 13: The average of 5, 7, 9, 11, 13 is ……… Câu số 17: 1/5 of 2m = ……….mm Câu số 18: Calculate: 1524 × 7 = …………. Câu số 19: If A is divisible by 4, then the remainder of A : 2 is …….. Câu số 20: If m = 10; n = 5; p = 2 then m + n + p + 3 =…….. Câu số 21: If the perimeter of a square is 104m then its one side’s length is ……m Câu số 22: Write the missing number: 4563005 - ………..= 2146356 Câu số 23: The average of three consecutive natural numbers is 37. The smallest number is…………. ko cần giải thích chỉ cần đáp án 5 sao thank