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Use the following steps to multiply mentally by 25.

• Divide the number by 4.
• If the remainder is 0, write 00 after the quotient.
• If the remainder is 1, write 25 after the quotient.
• If the remainder is 2, write 50 after the quotient.
• If the remainder is 3, write 75 after the quotient.

Example:

89 × 25 =

Divide 89 by 4.

89 ÷ 4 = 22 (remainder = 1)

Since the remainder is 1, write 25 after 22.

89 × 25 = 2225.

Example:

474 × 25 =

Divide 474 by 4.

474 ÷ 4 = 118 (remainder = 2)

Since the remainder is 2, write 50 after 118.

474 × 25 = 11850.